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Table Of Contents
Release Notes for Cisco 1700 Series Routers for Cisco IOS Release 12.3(8)XX2e
Determining the Software Version
Upgrading to a New Software Release
New Hardware Features in Cisco IOS Release12.3(8)XX2E
New Software Features in Cisco IOS Release12.3(8)XX2D
New Hardware Features in Cisco IOS Release12.3(8)XX2D
New Software Features in Cisco IOS Release12.3(8)XX2C
New Hardware Features in Cisco IOS Release 12.3(8)XX2b
New Software Features in Cisco IOS Release 12.3(8)XX2a
New Software Features in Cisco IOS Release 12.3(8)XX2
New Software Features in Cisco IOS Release 12.3(8)XX1
New Software Features in Cisco IOS Release 12.3(8)XX
New Software Features in Cisco IOS Release 12.3(8)T
Resolved Caveats - Cisco IOS Release 12.3(8)XX2e
Resolved Caveats - Cisco IOS Release 12.3(8)XX2d
Resolved Caveats - Cisco IOS Release 12.3(8)XX2c
Resolved Caveats - Cisco IOS Release 12.3(8)XX2D2b
Resolved Caveats - Cisco IOS Release 12.3(8)XX2Da
Resolved Caveats - Cisco IOS Releases 12.3(8)XX1 and 12.(8)XX2
Cisco IOS Software Documentation Set
Obtaining Documentation, Obtaining Support, and Security Guidelines
Release Notes for Cisco 1700 Series Routers for Cisco IOS Release 12.3(8)XX2e
August 08, 2007
0L-6269-09These release notes cover the limited release of the c1700-advsecurityk9-mz image for Cisco 1700 series routers.
New features and significant software components for the Cisco 1700 series routers that support the Cisco IOS Release 12.3(8)T, up to and including Cisco IOS Release 12.3(8)XX2E, are documented. These release notes are updated as needed to describe new memory requirements, new features, new hardware support, software platform deferrals, microcode or modem code changes, related document changes, and any other important changes. Use these release notes with the Cross-Platform Release Notes for Cisco IOS Release 12.3T located on Cisco.com.
For a list of the software caveats that apply to Cisco IOS Release 12.3(8)XX2E, see the "Caveats" section and Caveats for Cisco IOS Release 12.3(8)T. The online caveats document is updated for every maintenance release and is located on Cisco.com.
Contents
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Obtaining Documentation, Obtaining Support, and Security Guidelines
System Requirements
This section describes the system requirements for Cisco IOS Cisco IOS Release 12.3(8)XX2E and includes the following sections:
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Memory Requirements
Table 1 describes the memory requirements for the Cisco IOS feature sets that are supported by the Cisco IOS Release 12.3(8)XX2E on the Cisco 1700 series routers.
Hardware Supported
Cisco IOS Cisco IOS Release 12.3(8)XX2E supports the following Cisco 1700 series routers:
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The Cisco 1701, Cisco 1711, Cisco 1712, and Cisco 1721 routers run only data images. The Cisco 1751, Cisco 1751-V, and Cisco 1760 routers run data or data-and-voice images, providing digital and analog voice support. The Cisco 1711 and Cisco 1712 routers run select IP Security (IPSec) Triple Data Encryption Standard (3DES) images only (the Cisco 1700 IOS IP/ADSL/IPX/AT/IBM/FW/IDS PLUS IPSEC 3DES, the Cisco 1700 IOS IP/ADSL/FW/IDS PLUS IPSEC 3DES, the Cisco 1700 IOS ADVANCED SECURITY, the Cisco 1700 IOS ADVANCED IP SERVICES, and the Cisco 1700 IOS ADVANCED ENTERPRISE SERVICES images).
For descriptions of existing hardware features and supported modules, see the hardware installation guides, configuration and command reference guides, and additional documents specific to the Cisco 1700 series routers. These documents are available on Cisco.com at the following location:
http://www.cisco.com/univercd/cc/td/doc/product/access/acs_mod/1700/index.htm
Determining the Software Version
To determine which version of the Cisco IOS software is currently running on your Cisco 1700 series router, log in to the router and enter the show version command. The following sample output from the show version command indicates the version number.
Router> show versionCisco Internetwork Operating System SoftwareCisco IOS Software, C1700 Software (C1700-Y7-MZ), Version 12.3(8)XX2e, RELEASE SOFTWARE (fc1)Synched to technology version 12.3(7.11)TUpgrading to a New Software Release
For general information about upgrading to a new software release, see Cisco IOS Software Releases 12.3 T Installation and Upgrade Procedures located on Cisco.com.
Feature Set Tables
The Cisco IOS software is packaged in feature sets consisting of software images, depending on the platform. Each feature set contains a specific set of Cisco IOS features. Release 12.3(8)XX2D supports the same feature sets as Releases 12.3 and 12.3(8)T, but Release 12.3(8)XX2D includes new features supported by the Cisco 1700 series routers. Cisco IOS Release 12.3(8)XX2E is a rebuild of Release 12.3(8)XX2D and includes only bug fixes; it does not include any new features.
Caution
Table 2 through Table 4, Part 2 list the feature and feature sets supported in the Cisco IOS Cisco IOS Release 12.3(8)XX2E. The tables use the following conventions:
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Note
Table 2 Feature List by Cisco 1700 Legacy Feature Set for Cisco 1751, 1751-V, and 1760 Routers
FW/IDS PLUS IPSEC 3DES
AT/IBM/VOX/
FW/IDS PLUS IPSEC 3DESARP1 —Auto Logoff
12.3(8)XX2D
Yes
Yes
Yes
1 ARP = Address Resolution Protocol.
Table 3 Feature List by Cisco 1700 Legacy Feature Set for Cisco 1721, 1751, 1751-V, and 1760 Routers
IBM PLUS
IDS PLUS IPSEC 3DES
AT/IBM/FW/
IDS PLUS IPSEC 3DESARP—Auto Logoff1
12.3(8)XX2D
Yes
Yes
Yes
Yes
Yes
Yes
1 The ARP—Auto Logoff feature is not supported on Cisco 1720 router.
Table 4, Part 2 Feature List by Cross-Platform Feature Set for Cisco 1701, 1711, 1712, 1721, 1751, 1751-V, and 1760 Routers
ARP—Auto Logoff
12.3(8)XX2D
Yes
Yes
Yes
1 This image is supported only on Cisco 1751, 1751-V, and 1760 routers.
New and Changed Information
Cisco IOS Release 12.3(8)XX2C supports the features described in this section.
New Hardware Features in Cisco IOS Release12.3(8)XX2E
There are no new hardware features in this release.
New Software Features in Cisco IOS Release12.3(8)XX2D
There are no new software features in this release.
New Hardware Features in Cisco IOS Release12.3(8)XX2D
There are no new software features in this release.
New Software Features in Cisco IOS Release12.3(8)XX2C
There are no new software features in this release.
New Hardware Features in Cisco IOS Release 12.3(8)XX2b
There are no new software features in this release.
New Software Features in Cisco IOS Release 12.3(8)XX2a
There are no new software features in this release.
New Software Features in Cisco IOS Release 12.3(8)XX2
There are no new software features in this release.
New Software Features in Cisco IOS Release 12.3(8)XX1
There are no new software features in this release.
New Software Features in Cisco IOS Release 12.3(8)XX
The following sections describe the new software features supported by the Cisco 1700 series routers for Cisco IOS Release 12.3(8)XX.
ARP—Auto Logoff
The Address Resolution Protocol (ARP)—Auto Logoff feature overcomes a limitation of the current Authorized ARP Feature which causes premature log-off of peers. The ARP—Auto Logoff feature provides control for the probing of authorized peers, thus yielding more accurate detection of a peer's state of activity. The ARP—Auto Logoff feature permits configuration of how soon (interval) a peer will be probed and the maximum number of probes (count).
The new ARP probe function is enabled on an interface by the new interface configuration command arp probe interval <1-10> count <1-60>. The no form of the command is used to disable the function. The configuration is limited to, but not enforced on, the interface that has authorized ARP running.
The interval value specifies how soon a peer router will be probed if no reply is received from it. The count specifies the maximum number of probes.
The probing of a peer is triggered by the ARP timeout value for the interface. This value is calculated by the ARP timestamp and the configured ARP timeout value on the interface. Therefore, the actual probe starting time is calculated on the basis of the last ARP reply probe received from the peer.
To verify that the ARP probing process is running, use the show cpu process | in ARP command.
New Software Features in Cisco IOS Release 12.3(8)T
For information regarding the features supported in Cisco IOS Release 12.3(8)T, see the Cross-Platform Release Notes and New Feature Documentation links at the following location on Cisco.com:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123relnt/xprn123/index.htm
Limitations and Restrictions
The following sections describe the limitations and restrictions that apply to the Cisco 1700 series routers for Cisco IOS Cisco IOS Release 12.3(8)XX2E.
ARP—Auto Logoff
The ARP—Auto Logoff feature requires authorized ARP, DHCP, and secure ARP to be enabled on the interface.
Caveats
Caveats describe unexpected behavior or defects in the Cisco IOS software releases. Severity 1 caveats are the most serious caveats, severity 2 caveats are less serious, and severity 3 caveats are the least serious of these three severity levels.
Caveats in Cisco IOS Release 12.3(8)T are also in Cisco IOS Cisco IOS Release 12.3(8)XX2E. For information on caveats in Cisco IOS Release 12.3(2)T, see the Caveats for Cisco IOS Release 12.3(8)T document. This document lists severity 1 and 2 caveats; the documents is located on Cisco.com.
Note
Resolved Caveats - Cisco IOS Release 12.3(8)XX2e
CSCsd81407Multiple voice-related vulnerabilities are identified in Cisco IOS software, one of which is also shared with Cisco Unified Communications Manager. These vulnerabilities pertain to the following protocols or features:
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Cisco has made free software available to address these vulnerabilities for affected customers. Fixed Cisco IOS software listed in the Software Versions and Fixes section contains fixes for all vulnerabilities mentioned in this advisory.
There are no workarounds available to mitigate the effects of any of the vulnerabilities apart from disabling the protocol or feature itself.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20070808-IOS-voice.shtml
CSCsg70474Multiple voice-related vulnerabilities are identified in Cisco IOS software, one of which is also shared with Cisco Unified Communications Manager. These vulnerabilities pertain to the following protocols or features:
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Cisco has made free software available to address these vulnerabilities for affected customers. Fixed Cisco IOS software listed in the Software Versions and Fixes section contains fixes for all vulnerabilities mentioned in this advisory.
There are no workarounds available to mitigate the effects of any of the vulnerabilities apart from disabling the protocol or feature itself.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20070808-IOS-voice.shtml
CSCsi01470A vulnerability in the Cisco implementation of Multicast Virtual Private Network (MVPN) is subject to exploitation that can allow a malicious user to create extra multicast states on the core routers or receive multicast traffic from other Multiprotocol Label Switching (MPLS) based Virtual Private Networks (VPN) by sending specially crafted messages.
Cisco has released free software updates that address this vulnerability. Workarounds that mitigate this vulnerability are available.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20080326-mvpn.shtml.
CSCsi60004Multiple voice-related vulnerabilities are identified in Cisco IOS software, one of which is also shared with Cisco Unified Communications Manager. These vulnerabilities pertain to the following protocols or features:
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Cisco has made free software available to address these vulnerabilities for affected customers. Fixed Cisco IOS software listed in the Software Versions and Fixes section contains fixes for all vulnerabilities mentioned in this advisory.
There are no workarounds available to mitigate the effects of any of the vulnerabilities apart from disabling the protocol or feature itself.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20070808-IOS-voice.shtml
CSCse68138Multiple voice-related vulnerabilities are identified in Cisco IOS software, one of which is also shared with Cisco Unified Communications Manager. These vulnerabilities pertain to the following protocols or features:
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Cisco has made free software available to address these vulnerabilities for affected customers. Fixed Cisco IOS software listed in the Software Versions and Fixes section contains fixes for all vulnerabilities mentioned in this advisory.
There are no workarounds available to mitigate the effects of any of the vulnerabilities apart from disabling the protocol or feature itself.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20070808-IOS-voice.shtml
CSCef77013Cisco IOS and Cisco IOS XR contain a vulnerability when processing specially crafted IPv6 packets with a Type 0 Routing Header present. Exploitation of this vulnerability can lead to information leakage on affected Cisco IOS and Cisco IOS XR devices, and may also result in a crash of the affected Cisco IOS device. Successful exploitation on an affected device running Cisco IOS XR will not result in a crash of the device itself, but may result in a crash of the IPv6 subsystem.
Cisco has made free software available to address this vulnerability for affected customers. There are workarounds available to mitigate the effects of the vulnerability.
This advisory is posted at
http://www.cisco.com/warp/public/707/cisco-sa-20070808-IOS-IPv6-leak.shtml.
CSCsj66513 Traceback detected at DNQueuePeersSymptom Traceback found at DNQueuePeers
Conditions
Workaround
CSCdz55178 QoS profile name of more then 32 chars will crash the routerSymptom System reloads unexpectedly or other serious side-affects such as memory corruption occur.
Conditions
For example:
cable qos profile 12 name g711@10ms_for_any_softswitch_Traa^C00000000011111111111222222222333^12345678901234567890123456789012||PROBLEM (Variable Overflowed).Workaround
Further Problem Description: The variable which holds the value for the string name only allows for 32 characters and the code did not properly truncate names longer than the associated buffer.This corrupts memory in other locations.
CSCsj52927 DATACORRUPTION-1-DATAINCONSISTENCY message in show logSymptom DATACORRUPTION-1-DATAINCONSISTENCY messages are seen in `show log'.
Conditions
Workaround
CSCsj66369 Traceback seen at rpmxf_dg_db_initSymptom Tracebacks seen while running metal_vpn_cases.itcl script
Conditions
Workaround
CSCsj44099 Router crashes if DSPFARM profile description is 128 characters long.Symptom A cisco c3800 router can experience a memory corruption resulting in a crash if the description field under the "dspfarm profile" configuration matches the maximum of 128 characters.
Conditions
Workaround
CSCsj16292 DATACORRUPTION-1-DATAINCONSISTENCY: copy errorSymptom Following an upgrade to Cisco IOS Release 12.2(18)SXF9, the following message may be displayed:
%DATACORRUPTION-1-DATAINCONSISTENCY: copy error-Traceback=
Conditions
Workaround
CSCef61610 Incorrect handling of ICMPv6 messages can cause TCP performance problemsA document that describes how the Internet Control Message Protocol (ICMP)could be used to perform a number of Denial of Service (DoS) attacks against the Transmission Control Protocol (TCP) has been made publicly available. This document has been published through the Internet Engineering Task Force (IETF) Internet Draft process, and is entitled "ICMP Attacks Against TCP".
(draft-gont-tcpm-icmp-attacks-03.txt).
These attacks, which only affect sessions terminating or originating on a device itself, can be of three types:
1.
2.
3.
Successful attacks may cause connection resets or reduction of throughput in existing connections, depending on the attack type. Multiple Cisco products are affected by the attacks described in this Internet draft.
Cisco has made free software available to address these vulnerabilities. In some cases there are workarounds available to mitigate the effects of the vulnerability.This advisory is posted at: http://www.cisco.com/warp/public/707/cisco-sa-20050412-icmp.shtml.
The disclosure of these vulnerabilities is being coordinated by the National Infrastructure Security Coordination Centre (NISCC), based in the United Kingdom. NISCC is working with multiple vendors whose products are potentially affected. Its posting can be found at: http://www.niscc.gov.uk/niscc/docs/re-20050412-00303.pdf?lang=en.
CSCsg03449 Etherswitch module VLAN Trunking Protocol VulnerabilitiesSymptom
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Conditions
Further Information: On the 13th September 2006, Phenoelit Group posted an advisory containing three vulnerabilities:
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These vulnerabilities are addressed by Cisco IDs:
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Cisco's statement and further information are available on the Cisco public website at: http://www.cisco.com/warp/public/707/cisco-sr-20060913-vtp.shtml
CSCsb11124 SGBP Crafted Packet Denial of ServiceThe Cisco IOS Stack Group Bidding Protocol (SGBP) feature in certain versions of Cisco IOS software is vulnerable to a remotely-exploitable denial of service condition. Devices that do not support or have not enabled the SGBP protocol are not affected by this vulnerability.
Cisco has made free software available to address this vulnerability for affected customers. There are workarounds available to mitigate the effects of the vulnerability. Cisco has published a Security Advisory on this issue; it is available at: http://www.cisco.com/warp/public/707/cisco-sa-20060118-sgbp.shtml
CSCef48336 Corrupted OSPF Hello packets caused software forced crashOSPF is a routing protocol defined by RFC 2328. It is designed to manage IP routing inside an Autonomous System (AS). OSPF packets use IP protocol number 89. A vulnerability exists in the processing of an OSPF packet that can be exploited to cause the reload of a system.
Since OSPF needs to process unicast packets as well as multicast packets, this vulnerability can be exploited remotely. It is also possible for an attacker to target multiple systems on the local segment at a time.
Using OSPF Authentication can be used to mitigate the effects of this vulnerability. Using OSPF Authentication is a highly recommended security best practice. A Cisco device receiving a malformed OSPF packet will reset and may take several minutes to become fully functional. This vulnerability may be exploited repeatedly resulting in an extended DOS attack.
Workaround
Refer to http://www.cisco.com/warp/public/104/25.shtml for more information about OSPF authentication. Infrastructure Access Control Lists Although it is often difficult to block traffic transiting your network, it is possible to identify traffic which should never be allowed to target your infrastructure devices and block that traffic at the border of your network. Infrastructure ACLs are considered a network security best practice and should be considered as a long-term addition to good network security as well as a workaround for this specific vulnerability. The white paper "Protecting Your Core: Infrastructure Protection Access Control Lists" presents guidelines and recommended deployment techniques for infrastructure protection ACLs: http://www.cisco.com/warp/public/707/iacl.html
CSCsb93407 H323 port tcp 1720 still listening after call service stopSymptom When H323 call service stops, the router still listens on TCP port 1720 and completes connection attempts.
Conditions
voice service voip
h323
call service stop
Workaround
For further information about deploying access lists, see the "Protecting Your Core: Infrastructure Protection Access Control Lists" document at: http://www.cisco.com/warp/public/707/iacl.html.
For information about using control plane policing to block access to TCP port 1720, see the "Deploying Control Plane Policing White Paper" at: http://www.cisco.com/en/US/products/ps6642/products_white_paper0900aecd804fa16a.shtml.
CSCsf28840 Crash due to configured peer type control vectorA vulnerability exists in the Data-link Switching (DLSw) feature in Cisco IOS where an invalid value in a DLSw message could result in a reload of the DLSw device. Successful exploitation of this vulnerability requires that an attacker be able to establish a DLSw connection to the device.
There are workarounds available for this vulnerability.
This advisory is posted at: http://www.cisco.com/warp/public/707/cisco-sa-20070110-dlsw.shtml
CSCsa54608 IOS Firewall Auth-Proxy for FTP/Telnet Sessions buffer overflowThe Cisco IOS Firewall Authentication Proxy for FTP and/or Telnet Sessions feature in specific versions of Cisco IOS software is vulnerable to a remotely-exploitable buffer overflow condition. Devices that do not support, or are not configured for Firewall Authentication Proxy for FTP and/or Telnet Services are not affected.
Devices configured with only Authentication Proxy for HTTP and/or HTTPS are not affected. Only devices running certain versions of Cisco IOS are affected. Cisco has made free software available to address this vulnerability. There are workarounds available to mitigate the effects of the vulnerability. This advisory will be posted at: http://www.cisco.com/warp/public/707/cisco-sa-20050907-auth_proxy.shtml
CSCee45312 Radius authentication bypass when configured with a none fallback methodRemote Authentication Dial In User Service (RADIUS) authentication on a device that is running certain versions of Cisco Internetworking Operating System (IOS) and configured with a fallback method to none can be bypassed. Systems that are configured for other authentication methods or that are not configured with a fallback method to none are not affected.
Only the systems that are running certain versions of Cisco IOS are affected. Not all configurations using RADIUS and none are vulnerable to this issue. Some configurations using RADIUS, none and an additional method are not affected.
Cisco has made free software available to address this vulnerability. There are workarounds available to mitigate the effects of the vulnerability.
More details can be found in the security advisory which posted at the following URL: http://www.cisco.com/warp/public/707/cisco-sa-20050629-aaa.shtml
CSCei61732 Additional data integrity check in system timerCisco IOS may permit arbitrary code execution after exploitation of a heap-based buffer overflow vulnerability. Cisco has included additional integrity checks in its software, as further described below, that are intended to reduce the likelihood of arbitrary code execution.
Cisco has made free software available that includes the additional integrity checks for affected customers.
This advisory is posted at: http://www.cisco.com/warp/public/707/cisco-sa-20051102-timers.shtml
CSCef68324 ICMPv6 pkt tracebackCisco Internetwork Operating System (IOS®) Software is vulnerable to a Denial of Service (DoS) and potentially an arbitrary code execution attack from a specifically crafted IPv6 packet. The packet must be sent from a local network segment. Only devices that have been explicitly configured to process IPv6 traffic are affected. Upon successful exploitation, the device may reload or be open to further exploitation. Cisco has made free software available to address this vulnerability for all affected customers. More details can be found in the security advisory that is posted at: http://www.cisco.com/warp/public/707/cisco-sa-20050729-ipv6.shtml
CSCsj18014 Caller ID string received with extra charactersSymptom A caller ID may be received with extra characters.
Conditions
Workaround
CSCsb79076 MGCP RSVP enabled calls fails due to spurious error @ qosmodule_main%SYS-3-TIMERNEG errors and tracebacks are observed while making MGCP RSVP calls on a analog (RGW) setups. Observed in 12.4(3.9)T1 IOS version.
Workaround
CSCsg40567 Memory leak found with malformed tls/ssl packets in http core processSymptom Malformed SSL packets may cause a router to leak multiple memory blocks.
Conditions
Workaround
CSCin95836 Buffer overflow in NHRP protocolSymptom A Cisco IOS device configured for NHRP may restart.
Workaround
Resolved Caveats - Cisco IOS Release 12.3(8)XX2d
CSCsf04754Multiple Cisco products contain either of two authentication vulnerabilities in the Simple Network Management Protocol version 3 (SNMPv3) feature. These vulnerabilities can be exploited when processing a malformed SNMPv3 message. These vulnerabilities could allow the disclosure of network information or may enable an attacker to perform configuration changes to vulnerable devices. The SNMP server is an optional service that is disabled by default. Only SNMPv3 is impacted by these vulnerabilities. Workarounds are available for mitigating the impact of the vulnerabilities described in this document.
The United States Computer Emergency Response Team (US-CERT) has assigned Vulnerability Note VU#878044 to these vulnerabilities.
Common Vulnerabilities and Exposures (CVE) identifier CVE-2008-0960 has been assigned to these vulnerabilities.
This advisory will be posted at http://www.cisco.com/warp/public/707/cisco-sa-20080610-snmpv3.shtml
CSCin95836The Cisco Next Hop Resolution Protocol (NHRP) feature in Cisco IOS contains a vulnerability that can result in a restart of the device or possible remote code execution.
NHRP is a primary component of the Dynamic Multipoint Virtual Private Network (DMVPN) feature.
NHRP can operate in three ways: at the link layer (Layer 2), over Generic Routing Encapsulation (GRE) and multipoint GRE (mGRE) tunnels and directly on IP (IP protocol number 54). This vulnerability affects all three methods of operation.
NHRP is not enabled by default for Cisco IOS.
This vulnerability is addressed by Cisco bug IDs CSCin95836 for non-12.2 mainline releases and CSCsi23231 for 12.2 mainline releases.
This advisory is posted at
http://www.cisco.com/warp/public/707/cisco-sa-20070808-nhrp.shtml.
CSCsb12598Cisco IOS device may crash while processing malformed Secure Sockets Layer (SSL) packets. In order to trigger these vulnerabilities, a malicious client must send malformed packets during the SSL protocol exchange with the vulnerable device.
Successful repeated exploitation of any of these vulnerabilities may lead to a sustained Denial-of-Service (DoS); however, vulnerabilities are not known to compromise either the confidentiality or integrity of the data or the device. These vulnerabilities are not believed to allow an attacker will not be able to decrypt any previously encrypted information.
Cisco IOS is affected by the following vulnerabilities:
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Cisco has made free software available to address these vulnerabilities for affected customers. There are workarounds available to mitigate the effects of these vulnerabilities.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20070522-SSL.shtml.
CSCsb40304Cisco IOS device may crash while processing malformed Secure Sockets Layer (SSL) packets. In order to trigger these vulnerabilities, a malicious client must send malformed packets during the SSL protocol exchange with the vulnerable device.
Successful repeated exploitation of any of these vulnerabilities may lead to a sustained Denial-of-Service (DoS); however, vulnerabilities are not known to compromise either the confidentiality or integrity of the data or the device. These vulnerabilities are not believed to allow an attacker will not be able to decrypt any previously encrypted information.
Cisco IOS is affected by the following vulnerabilities:
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Cisco has made free software available to address these vulnerabilities for affected customers. There are workarounds available to mitigate the effects of these vulnerabilities.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20070522-SSL.shtml.
Note
A combined software table for Cisco IOS is available to aid customers in choosing a software releases that fixes all security vulnerabilities published as of May 22, 2007. This software table is available at the following link: http://www.cisco.com/warp/public/707/cisco-sa-20070522-cry-bundle.shtml.
CSCsd85587A vulnerability has been discovered in a third party cryptographic library which is used by a number of Cisco products. This vulnerability may be triggered when a malformed Abstract Syntax Notation One (ASN.1) object is parsed. Due to the nature of the vulnerability it may be possible, in some cases, to trigger this vulnerability without a valid certificate or valid application-layer credentials (such as a valid username or password).
Successful repeated exploitation of any of these vulnerabilities may lead to a sustained Denial-of-Service (DoS); however, vulnerabilities are not known to compromise either the confidentiality or integrity of the data or the device. These vulnerabilities are not believed to allow an attacker will not be able to decrypt any previously encrypted information.
The vulnerable cryptographic library is used in the following Cisco products:
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This vulnerability is also being tracked by CERT/CC as VU#754281.
Cisco has made free software available to address this vulnerability for affected customers. There are no workarounds available to mitigate the effects of the vulnerability.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20070522-crypto.shtml.
Note
CSCsd92405Cisco IOS device may crash while processing malformed Secure Sockets Layer (SSL) packets. In order to trigger these vulnerabilities, a malicious client must send malformed packets during the SSL protocol exchange with the vulnerable device.
Successful repeated exploitation of any of these vulnerabilities may lead to a sustained Denial-of-Service (DoS); however, vulnerabilities are not known to compromise either the confidentiality or integrity of the data or the device. These vulnerabilities are not believed to allow an attacker will not be able to decrypt any previously encrypted information.
Cisco IOS is affected by the following vulnerabilities:
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Cisco has made free software available to address these vulnerabilities for affected customers. There are workarounds available to mitigate the effects of these vulnerabilities.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20070522-SSL.shtml.
Note
A combined software table for Cisco IOS is available to aid customers in choosing a software releases that fixes all security vulnerabilities published as of May 22, 2007. This software table is available at the following link: http://www.cisco.com/warp/public/707/cisco-sa-20070522-cry-bundle.shtml.
CSCed95187 IP ID field is predictable for connectionless RST packetsSymptom RST packets sent in response to a TCP SYN packet received by the device on a non-listening port contain a non-randomized Identification value on the IP header.
Conditions
Workaround
Further Problem Description: From RFC791, the description of the Identification field is:
Identification
The choice of the Identifier for a datagram is based on the need to provide a way to uniquely identify the fragments of a particular datagram. The protocol module assembling fragments judges fragments to belong to the same datagram if they have the same source, destination, protocol, and Identifier. Thus, the sender must choose the Identifier to be unique for this source, destination pair and protocol for the time the datagram (or any fragment of it) could be alive in the internet.It seems then that a sending protocol module needs to keep a table of Identifiers, one entry for each destination it has communicated with in the last maximum packet lifetime for the internet.
Also from RFC791: The IP ID is before the flags and fragment offset fields.
For Example: Internet Datagram header
3.1. Internet Header Format
A summary of the contents of the internet header follows:
0 1 2 30 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+|Version| IHL |Type of Service| Total Length |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Identification |Flags| Fragment Offset |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Time to Live | Protocol | Header Checksum |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Source Address |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Destination Address |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| Options | Padding |+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+CSCse95758 Access Lists support for all CONFIG-COPY-MIB protocols under snmp-serverSymptom Customers can use an access list to restrict TFTP configuration transfers that are initiated via SNMP by using the command snmp-servertftp-server-list access-list. This restriction is not possible for the FTP, RCP, and SCP protocols.
Conditions
access-list 5 permit 10.1.1.1
snmp-server community private RW 5
snmp-server tftp-server-list 5
Workaround
1.
2.
3.
Fixed Software Information:
Access-List Support for CISCO-CONFIG-COPY-MIB The snmp-server file-transfer access-group command is introduced to restrict configuration transfers that are initiated via the Simple Network Management Protocol (SNMP). Supported transfer protocols are TFTP, FTP, Remote Copy Protocol (RCP), Secure Copy Protocol (SCP), and Secured File Transfer Protocol (SFTP).
This command replaces the snmp-server tftp-server-list command.
For detailed information about the snmp-server file-transfer access-group command, see the Cisco IOS Network Management Command Reference, Release 12.4.
CSCek26492 Enhancements to Packet Input Path.Symptom A router may crash if it receives a packet with a specific crafted IP option as detailed in Cisco Security Advisory: Crafted IP Option Vulnerability:
http://www.cisco.com/warp/public/707/cisco-sa-20070124-crafted-ip-option.shtml
Conditions
Workaround
http://www.cisco.com/warp/public/707/cisco-sa-20070124-crafted-ip-option.shtml
CSCsd92405 Router crashed by repeated SSL connection with malformed finished messageSymptom A router crashes when receiving multiple malformed TLS and/or SSL3 finished messages. A valid username and password are not required for the crash to occur.
Conditions
Workaround
CSCed94829 IOS reloads due to malformed IKE messagesMultiple Cisco products contain vulnerabilities in the processing of IPSec IKE (Internet Key Exchange) messages. These vulnerabilities were identified by the University of Oulu Secure Programming Group (OUSPG) "PROTOS" Test Suite for IPSec and can be repeatedly exploited to produce a denial of service.
Cisco has made free software available to address this vulnerability for affected customers. Prior to deploying software, customers should consult their maintenance provider or check the software for feature set compatibility and known issues specific to their environment.
This advisory is posted at:
http://www.cisco.com/warp/public/707/cisco-sa-20051114-ipsec.shtml.
CSCed09685 IOS should not send passwords and sensitive information to ACS logs.Symptom When command accounting is enabled, Cisco IOS routers will send the full text of each command to the ACS server. Though this information is sent to the server encrypted, the server will decrypt the packet and log these commands to the logfile in plain text. Thus sensitive information like passwords will be visible in the server's log files.
Conditions
Workaround
CSCsc72722 CBAC - firewall resets TCP idle timer upon receiving invalid TCP packetsSymptom TCP connections that are opened through a Cisco IOS Firewall (CBAC) may not timeout.
Conditions
Workaround
CSCsa53334 Bus error in single_pkt_regexThe Intrusion Prevention System (IPS) feature set of Cisco IOS® contains
several vulnerabilities. These include:
•
•
There are mitigations and workarounds for these vulnerabilities. Cisco has made free software available to address these vulnerabilities for affected customers.
This advisory is posted at:
http://www.cisco.com/warp/public/707/cisco-sa-20070213-iosips.shtml
CSCsc44237 Memory leak in client applications iterating over an empty idb list
Note
Symptom 1 A switch or router that is configured with a PA-A3 ATM port adapter may eventually run out of memory. The leak occurs when the FlexWAN or VIP that contains the PA-A3 port adapter is removed from the switch or router and not re-inserted.The output of the show processes memory command shows that the "ATM PA Helper" process does not have sufficient memory. The output of the show memory allocating-process totals command shows that the "Iterator" process holds the memory.
Conditions
http://www.cisco.com/pcgi-bin/Support/Bugtool/onebug.pl?bugid=CSCeh04646 and
http://www.cisco.com/pcgi-bin/Support/Bugtool/onebug.pl?bugid=CSCeb30831
Cisco IOS software releases that are not listed in the "First Fixed-in Version" fields at these locations are not affected.
Workaround
Symptom 2: A switch or router that has certain PIM configurations may eventually run out of memory.The output of the show processes memory command shows that the "PIM process" does not have sufficient memory. The output of the show memory allocating-process totals command shows that the "Iterator" process holds the memory.
Conditions
http://www.cisco.com/pcgi-bin/Support/Bugtool/onebug.pl?bugid=CSCef50104.
Cisco IOS software releases that are not listed in the "First Fixed-in Version" field at this location are not affected.
Workaround
CSCsg70355 Adopt new default summer-time rules from Energy Policy Act of 2005Symptom Starting in calendar year 2007, daylight savings summer-time rules may cause Cisco IOS to generate timestamps (such as in syslog messages) that are off by one hour.
Conditions
clock summer-time zone
recurring
uses United States standards for daylight savings time rules by default. The Energy Policy Act of 2005 (H.R.6.ENR), Section 110 changes the start date from the first Sunday of April to the second Sunday of March. It changes the end date from the last Sunday of October to the first Sunday of November.
Workaround
clock summer-time PDT
recurring 2 Sun Mar 2:00 1 Sun Nov
2:00
(This example is for the US/Pacific time zone.)
Not A Workaround: Using NTP is not a workaround to this problem. NTP does not carry any information about timezones or summertime.
CSCse24889 Malformed SSH version 2 packets may cause processor memory depletionSymptom Malformed SSH version 2 packets may cause a memory leak, causing the platform to operate under a degraded condition. Under rare circumstances, the platform may reload to recover itself.
Conditions
Workaround
config t
ip ssh version 1
end
Alternate Workaround: Permit only known trusted hosts and/or networks to connect to the router by creating a vty access list, as in the following example:
10.1.1.0/24 is a trusted network that is permitted access to the router,all other access is deniedaccess-list 99 permit 10.1.1.0 0.0.0.255access-list 99 deny anyline vty 0 4access-class 99 inendFurther Problem Description: For information about configuring vty access lists, see the Controlling Access to a Virtual Terminal Line document:
http://www.cisco.com/en/US/products/ps6441/products_configuration_guide_chapter09186a0080716ec2.html
For information about SSH, see the Configuring Secure Shell on Routers and Switches Running Cisco IOS document:
http://www.cisco.com/warp/public/707/ssh.shtml
CSCse85200 Inadequate validation of TLVs in cdpSymptom Specifically crafted CDP packets can cause a router to allocate and keep extra memory. Exploitation of this behavior by sending multiple specifically crafted CDP packets could cause memory allocation problems on the router.
Conditions
Workaround
CSCsa43465 None method in default login method list allows enabling with no passwdSymptom Users may be able to access root view mode (privilege level) 15 without entering a password.
Conditions
For example, the symptom may occur when you enter the aaa authentication login default group tacacs+ none. When the TACACS+ server is down, users are allowed to enter non-privileged mode. However, users can also access the root view through the enable view command without having to enter a password.
Workaround
Further Problem Description: The fix for this caveat places the authentication of the enable view command in the default login method list.
CSCse04560 tftp-server allows for information disclosureSymptom A tftp client trying to transfer a file from a Cisco IOS device configured as a tftp server and which is denied by an ACL receives a different result depending if the file is being offered for download or not. This may allow a third party to enumerate which files are available for download.
Conditions
tftp-serverflash:filename1access-list-numberaccess-list access-list-numberpermit 192.168.1.00.0.0.255access-list access-list-numberdeny anyWorkaround
1.
access-list access-list-numberremark --- the following hostsand networks areaALLOWED for TFTP accessaccess-list access-list-numberpermit udp hostsource_1hostinterface_address_1eq 69access-list access-list-numberpermit udp hostsource_2hostinterface_address_2eq 69access-list access-list-numberpermit udp source source-wildcardhostinterface_address_1eq 69access-list access-list-numberpermit udp source source-wildcardhostinterface_address_2eq 69access-list access-list-numberremark --- everyone else isDENIED for TFTPaccessaccess-list access-list-numberdeny udp any hostinterface_address_1eq 69access-list access-list-numberdeny udp any hostinterface_address_2eq 69access-list access-list-numberremark --- any other trafficto/through the routeris allowedaccess-list access-list-numberpermit ip any anyinterface Ethernet0/0ip access-group access-list-numberinOnce the tftp server in Cisco IOS is enabled and listening by default on all interfaces enabled for IP processing, the access list would need to deny traffic to each and every IP address assigned to any active router interface.
2.
access-list access-list-numberremark --- Do not police TFTPtraffic from trustedhosts and networksaccess-list access-list-numberdeny udp hostsource_1 anyeq 69access-list access-list-numberdeny udp source source-wildcardany eq 69access-list access-list-numberremark --- Police TFTP trafficfrom untrustedhosts and networksaccess-list access-list-numberpermit udp any any eq69access-list access-list-numberremark --- Do not police anyother traffic goingto the routeraccess-list access-list-numberdeny ip any anyclass-map match-all tftp-classmatch access-group access-list-numberpolicy-map control-plane-policy! Drop all traffic that matches the class tftp-classclass tftp-classdropcontrol-planeservice-policy input control-plane-policy
Note
3.
Note
CSCsb11849 CoPP: Need support for malformed IP optionsSymptom CoPP policy configured to drop packets with IP options will ignore packets with malformed IP options
Conditions
Workaround
CSCsc64976 HTTP server should scrub embedded HTML tags from cmd outputA vulnerability exists in the IOS HTTP server in which HTML code inserted into dynamically generated output, such as the output from a show buffers command, will be passed to the browser requesting the page. This HTML code could be interpreted by the client browser and potentially execute malicious commands against the device or other possible cross-site scripting attacks. Successful exploitation of this vulnerability requires that a user browse a page containing dynamic content in which HTML commands have been injected.
Cisco will be making free software available to address this vulnerability for affected customers. There are workarounds available to mitigate the effects of the vulnerability. This advisory is posted at:
http://www.cisco.com/warp/public/707/cisco-sa-20051201-http.shtml
CSCsg16908 IOS FTP Server DeprecationSymptom This bug documents the deprecation and removal of the Cisco IOS FTP Server feature.
Workaround
CSCse05736 A router running RCP can be reloaded with a specific packetSymptom A router that is running RCP can be reloaded by a specific packet.
Conditions
–
–
–
Workaround
CSCek37177 Malformed tcp packets deplete processor memory.The Cisco IOS Transmission Control Protocol (TCP) listener in certain versions of Cisco IOS software is vulnerable to a remotely-exploitable memory leak that may lead to a denial of service condition.
This vulnerability only applies to traffic destined to the Cisco IOS device. Traffic transiting the Cisco IOS device will not trigger this vulnerability. Cisco has made free software available to address this vulnerability for affected customers.
This issue is documented as Cisco bug ID CSCek37177. There are workarounds available to mitigate the effects of the vulnerability. This advisory is posted at:
http://www.cisco.com/warp/public/707/cisco-sa-20070124-crafted-tcp.shtml
CSCeh73049 tclsh mode bypasses aaa command authorization checkSymptom A vulnerability exists within the Cisco IOS Authentication, Authorization, and Accounting (AAA) command authorization feature, where command authorization checks are not performed on commands executed from the Tool Command Language (Tcl) exec shell. This may allow authenticated users to bypass command authorization checks in some configurations resulting in unauthorized privilege escalation.
Conditions
functionality are not affected by this vulnerability.This vulnerability is present in all versions of Cisco IOS that support the tclsh command.
Workaround
http://www.cisco.com/warp/public/707/cisco-response-20060125-aaatcl.shtml
CSCee24395 SYS-3-BADMAGIC after GetNextObjectInstance clogHistoryEntry_getSymptom A Cisco router may reload if SNMP GetNextObjectInstance request are processed at clogHistoryEntry_get.
Conditions
Workaround
CSCsc06695 IKEv1 SA leaks under certain conditionsSymptom When a Phase 1 SA (MM or AM) is being setup and the client does quick retransmissions within a window of one second, the server stops the restransmission timer for the SA. If the client stops retransmissions or further message afterwards, SA on server side is leaked forever (until the
lifetime timer expires).
Workaround
CSCsb33172 Short-circuit crypto engine operations when faking AM2A vulnerability exists in the way some Cisco products handle IKE phase I messages which allows an attacker to discover which group names are configured and valid on the device. A Cisco Security Notice has been published on this issue and can be found at the following URL:
http://www.cisco.com/warp/public/707/cisco-sn-20050624-vpn-grpname.shtml
CSCsb52717 Watchdog timeout and crash caused by invalid MDT data group join packetSymptom A Cisco router configured for multicast VPN may reload after receiving a malformed MDT data group join packet.
Conditions
Workaround
The following example shows how to block malformed MDT Data Join messages that are sent from the device's IP addresses using a receive ACL:
!ip receive access-list 111!access-list 111 deny udp host <ip address of router sending malformed joinrequest> host 224.0.0.13 eq 3232access-list 111 permit ip any any!
Note
As always, we recommend that you test this feature in the lab prior to deployment. For more information on rACLs, refer to "Protecting Your Core: Infrastructure Protection Access Control Lists" at: http://www.cisco.com/warp/public/707/racl.html.
CSCej30903 Enable View Command fails with AAA turned onSymptom A router allows logging into the root (or any other configured) view without prompting for a password.
Conditions
Workaround
CSCin95836 NHRP does not handle error conditions gracefullySymptom A Cisco IOS device configured for NHRP may restart.
Workaround
CSCei62522 ISAKMP SA negotiation not successfull in aggressive mode with RADIUSSymptom ISAKMP SA negotiation is not successful in aggressive mode.
Conditions
Workaround
Resolved Caveats - Cisco IOS Release 12.3(8)XX2c
CSCsb24007Multiple voice-related vulnerabilities are identified in Cisco IOS software, one of which is also shared with Cisco Unified Communications Manager. These vulnerabilities pertain to the following protocols or features:
–
–
–
–
–
Cisco has made free software available to address these vulnerabilities for affected customers. Fixed Cisco IOS software listed in the Software Versions and Fixes section contains fixes for all vulnerabilities mentioned in this advisory.
There are no workarounds available to mitigate the effects of any of the vulnerabilities apart from disabling the protocol or feature itself.
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20070808-IOS-voice.shtml
CSCef67682 Reception of certain IPv6 fragments with carefully crafted illegal contents may cause a router running Cisco IOS to reload if it has IPv6 configured. This applies to all versions of Cisco IOS that include support for IPv6.The system may be protected by installing appropriate access lists to filter all IPv6 fragments destined for the system. For example:interface Ethernet0/0ipv6 traffic-filter nofragments in!ipv6 access-list nofragmentsdeny ipv6 any <my address1> undetermined-transportdeny ipv6 any <my address2> fragmentspermit ipv6 any anyWorkaround
Note
CSCei61732Symptom Cisco IOS may permit arbitrary code execution after exploitation of a heap-based buffer overflow vulnerability. Cisco has included additional integrity checks in its software, as further described below, that are intended to reduce the likelihood of arbitrary code execution.
Workaround
CSCeg15044 You cannot telnet to card.CSCeh13489 BGP shouldn't propagate updates with AS PATH lengths greater than 255.CSCed03333Symptom CBAC sessions are left in sis-closing state due to out-of-order packet handling.
Workaround
CSCee45312Symptom Remote Authentication Dial In User Service (RADIUS) authentication on a device that is running certain versions of Cisco Internetworking Operating System (IOS) and configured with a fallback method to none can be bypassed.
Conditions
Workaround
More details can be found in the security advisory which posted at: http://www.cisco.com/warp/public/707/cisco-sa-20050629-aaa.shtml.
CSCed86842Symptom Negative Counters are encountered in the Input Queue.
Workaround
CSCee47441Symptom When the Cisco IOS Firewall CBAC is configured, the router has a software-forced reload caused by one of the processed inspections.
Conditions
Workaround
CSCef44699A document that describes how the Internet Control Message Protocol (ICMP) could be used to perform a number of Denial of Service (DoS) attacks against the Transmission Control Protocol (TCP) has been made publicly available. This document has been published through the Internet Engineering Task Force (IETF) Internet Draft process, and is entitled "ICMP Attacks Against TCP" (draft-gont-tcpm-icmp-attacks-03.txt).
These attacks, which only affect sessions terminating or originating on a device itself, can be of three types:
1. Attacks that use ICMP "hard" error messages.
2. Attacks that use ICMP "fragmentation needed and Don't Fragment (DF) bit set" messages, also known as Path Maximum Transmission Unit Discovery (PMTUD) attacks.
3. Attacks that use ICMP "source quench" messages.
Successful attacks may cause connection resets or reduction of throughput in existing connections, depending on the attack type.
Multiple Cisco products are affected by the attacks described in this Internet draft.
Workaround
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20050412-icmp.shtml.
The disclosure of these vulnerabilities is being coordinated by the National Infrastructure Security Coordination Centre (NISCC), based in the United Kingdom. NISCC is working with multiple vendors whose products are potentially affected. Its posting can be found at: http://www.niscc.gov.uk/niscc/docs/re-20050412-00303.pdf?lang=en.
CSCef61610A document that describes how the Internet Control Message Protocol (ICMP) could be used to perform a number of Denial of Service (DoS) attacks against the Transmission Control Protocol (TCP) has been made publicly available. This document has been published through the Internet Engineering Task Force (IETF) Internet Draft process, and is entitled "ICMP Attacks Against TCP" (draft-gont-tcpm-icmp-attacks-03.txt).
These attacks, which only affect sessions terminating or originating on a device itself, can be of three types:
1. Attacks that use ICMP "hard" error messages.
2. Attacks that use ICMP "fragmentation needed and Don't Fragment (DF) bit set" messages, also known as Path Maximum Transmission Unit Discovery (PMTUD) attacks.
3. Attacks that use ICMP "source quench" messages.
Successful attacks may cause connection resets or reduction of throughput in existing connections, depending on the attack type.
Multiple Cisco products are affected by the attacks described in this Internet draft.
Workaround
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20050412-icmp.shtml.
The disclosure of these vulnerabilities is being coordinated by the National Infrastructure Security Coordination Centre (NISCC), based in the United Kingdom. NISCC is working with multiple vendors whose products are potentially affected. Its posting can be found at: http://www.niscc.gov.uk/niscc/docs/re-20050412-00303.pdf?lang=en.
CSCsa54608The Cisco IOS Firewall Authentication Proxy for FTP and/or Telnet Sessions feature in specific versions of Cisco IOS software is vulnerable to a remotely-exploitable buffer overflow condition.
Conditions
Workaround
This advisory will be posted at: http://www.cisco.com/warp/public/707/cisco-sa-20050907-auth_proxy.shtml.
CSCsa52807A document that describes how the Internet Control Message Protocol (ICMP) could be used to perform a number of Denial of Service (DoS) attacks against the Transmission Control Protocol (TCP) has been made publicly available. This document has been published through the Internet Engineering Task Force (IETF) Internet Draft process, and is entitled "ICMP Attacks Against TCP" (draft-gont-tcpm-icmp-attacks-03.txt).
These attacks, which only affect sessions terminating or originating on a device itself, can be of three types:
1. Attacks that use ICMP "hard" error messages.
2. Attacks that use ICMP "fragmentation needed and Don't Fragment (DF) bit set" messages, also known as Path Maximum Transmission Unit Discovery (PMTUD) attacks.
3. Attacks that use ICMP "source quench" messages.
Successful attacks may cause connection resets or reduction of throughput in existing connections, depending on the attack type.
Multiple Cisco products are affected by the attacks described in this Internet draft.
Workaround
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20050412-icmp.shtml.
The disclosure of these vulnerabilities is being coordinated by the National Infrastructure Security Coordination Centre (NISCC), based in the United Kingdom. NISCC is working with multiple vendors whose products are potentially affected. Its posting can be found at: http://www.niscc.gov.uk/niscc/docs/re-20050412-00303.pdf?lang=en.
Resolved Caveats - Cisco IOS Release 12.3(8)XX2D2b
CSCef68324Symptom Cisco Internetwork Operating System (IOS) software is vulnerable to a Denial of Service (DoS) and potentially an arbitrary code execution attack from a specifically crafted IPv6 packet. The packet must be sent from a local network segment. Only devices that have been explicitly configured to process IPv6 traffic are affected. Upon successful exploitation, the device may reload or be open to further exploitation.
Workaround
More details can be found in the security advisory that is posted at: http://www.cisco.com/warp/public/707/cisco-sa-20050729-ipv6.shtml.
Resolved Caveats - Cisco IOS Release 12.3(8)XX2Da
CSCef43691 L2TPv3 and UTI sessions doing PMTUD vulnerable to spoofed ICMP paks.A document that describes how the Internet Control Message Protocol (ICMP) could be used to perform a number of Denial of Service (DoS) attacks against the Transmission Control Protocol (TCP) has been made publicly available. This document has been published through the Internet Engineering Task Force (IETF) Internet Draft process, and is entitled "ICMP Attacks Against TCP" (draft-gont-tcpm-icmp-attacks-03.txt).
These attacks, which only affect sessions terminating or originating on a device itself, can be of three types:
1. Attacks that use ICMP "hard" error messages.
2. Attacks that use ICMP "fragmentation needed and Don't Fragment (DF) bit set" messages, also known as Path Maximum Transmission Unit Discovery (PMTUD) attacks.
3. Attacks that use ICMP "source quench" messages.Successful attacks may cause connection resets or reduction of throughput in existing connections, depending on the attack type.
Multiple Cisco products are affected by the attacks described in this Internet draft.
Workaround
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20050412-icmp.shtml.
The disclosure of these vulnerabilities is being coordinated by the National Infrastructure Security Coordination Centre (NISCC), based in the United Kingdom. NISCC is working with multiple vendors whose products are potentially affected. Its posting can be found at: http://www.niscc.gov.uk/niscc/docs/re-20050412-00303.pdf?lang=en.
CSCef44225 IPSec (ESP-AH) doing PMTUD vulnerable to spoofed ICMP packets.See note for CSCef43691 above.CSCef60659 More stringent checks required for ICMP unreachables. See note for CSCef43691 above.CSCsa59600 IPSec PMTUD not working [after CSCef44225].See note for CSCef43691 above.Resolved Caveats - Cisco IOS Releases 12.3(8)XX1 and 12.(8)XX2
CSCec88490 Cosmetic Display CLI Related Issues.CSCed78149A document that describes how the Internet Control Message Protocol (ICMP) could be used to perform a number of Denial of Service (DoS) attacks against the Transmission Control Protocol (TCP) has been made publicly available. This document has been published through the Internet Engineering Task Force (IETF) Internet Draft process, and is entitled "ICMP Attacks Against TCP" (draft-gont-tcpm-icmp-attacks-03.txt).
These attacks, which only affect sessions terminating or originating on a device itself, can be of three types:
1. Attacks that use ICMP "hard" error messages.
2. Attacks that use ICMP "fragmentation needed and Don't Fragment (DF) bit set" messages, also known as Path Maximum Transmission Unit Discovery (PMTUD) attacks.
3. Attacks that use ICMP "source quench" messages.Successful attacks may cause connection resets or reduction of throughput in existing connections, depending on the attack type.
Multiple Cisco products are affected by the attacks described in this Internet draft.
Workaround
This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20050412-icmp.shtml.
The disclosure of these vulnerabilities is being coordinated by the National Infrastructure Security Coordination Centre (NISCC), based in the United Kingdom. NISCC is working with multiple vendors whose products are potentially affected. Its posting can be found at: http://www.niscc.gov.uk/niscc/docs/re-20050412-00303.pdf?lang=en.
CSCee67450A Cisco device running Cisco IOS and enabled for the Border Gateway Protocol (BGP) is vulnerable to a Denial of Service (DoS) attack from a malformed BGP packet. Only devices with the command `bgp log-neighbor-changes' configured are vulnerable. The BGP protocol is not enabled by default, and must be configured in order to accept traffic from an explicitly defined peer. Unless the malicious traffic appears to be sourced from a configured, trusted peer, it would be difficult to inject a malformed packet.
If a misformed packet is received and queued up on the interface, this bug may also be triggered by other means which are not considered remotely exploitable such as the use of the command `show ip bgp neighbors' or running the command `debug ip bgp <neighbor> updates' for a configured bgp neighbor.
Cisco has made free software available to address this problem.
For more details, please refer to this advisory, available at: http://www.cisco.com/warp/public/707/cisco-sa-20050126-bgp.shtml
CSCef46191 Unable to telnet.CSCef56396 IPSec SAs fail to come up for more than one ACL:NAT-T tunnel fails.CSCin82407Cisco Internetwork Operating System (IOS) Software release trains 12.2T, 12.3 and 12.3T may contain vulnerabilities in processing certain Internet Key Exchange (IKE) Xauth messages when configured to be an Easy VPN Server.
Workaround
Additional References
The following sections describe the documentation available for the Cisco 1700 series routers. These documents consist of hardware and software installation guides, Cisco IOS configuration guides and command references, system error messages, feature modules, and other documents.
Documentation is available as printed manuals or electronic documents, except for feature modules, which are available online on Cisco.com and http://www.cisco.com/univercd/home/index.htm.
Use these release notes with these documents:
•
Release-Specific Documents
The following documents are specific to Cisco IOS Release 12.3 and are located on Cisco.com and http://www.cisco.com/univercd/home/index.htm:
•
Note
•
http://www.cisco.com/univercd/home/index.htm
•
As a supplement to the caveats listed in these release notes, see Caveats for Cisco IOS Release 12.3 and Caveats for Cisco IOS Release 12.3T, which contain caveats applicable to all platforms for all maintenance releases of Cisco IOS Release 12.3 and Cisco IOS Release 12.3T.
•
Platform-Specific Documents
These documents are available for the Cisco 1700 series routers:
On Cisco.com at:
http://www.cisco.com/univercd/home/index.htm
Cisco IOS Software Documentation Set
The Cisco IOS software documentation set consists of the Cisco IOS configuration guides, Cisco IOS command references, and several other supporting documents.
Documentation Modules
Each module in the Cisco IOS documentation set consists of one or more configuration guides and one or more corresponding command references. Chapters in a configuration guide describe protocols, configuration tasks, and Cisco IOS software functionality, and contain comprehensive configuration examples. Chapters in a command reference provide complete command syntax information. Use each configuration guide with its corresponding command reference. Cisco IOS Software Documentation is available in html or pdf form.
Select your release and click the command references, configuration guides, or any other Cisco IOS documentation you need
Obtaining Documentation, Obtaining Support, and Security Guidelines
For information on obtaining documentation, obtaining support, providing documentation feed-back, security guidelines, and also recommended aliases and general Cisco documents, see the monthly What's New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation at:
http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html
Use this document in conjunction with the documents listed in the "Additional References" section.
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