Advisory ID: cisco-sa-20110706-csg
For Public Release 2011 July 6 16:00 UTC (GMT)
A denial of service (DoS) vulnerability exists in the Cisco Content
Services Gateway - Second Generation, that runs on the Cisco Service and
Application Module for IP (SAMI). An unauthenticated, remote attacker could
exploit this vulnerability by sending a series of crafted ICMP packets to an
affected device. Exploitation could cause the device to reload.
There are no workarounds available to mitigate exploitation
of this vulnerability other than blocking ICMP traffic destined to the affected
This advisory is posted at http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20110706-csg
All versions of the Cisco IOS Software for the Content Services
Gateway: Second Generation prior to the first fixed release are affected, as
indicated in the "Software Versions and Fixes" section of this advisory.
Determining Cisco CSG Software Versions
To determine the version of Cisco IOS Software that is running on the
Cisco CSG2, issue the "show module" command from Cisco IOS
Software on the switch on which the Cisco CSG2 module is installed to identify
what modules and sub-modules are installed on the system.
Cisco Content Services Gateway: Second Generation runs on the Cisco
Service and Application Module for IP (SAMI) card, and is identified in the
following example in slot 2 via the WS-SVC-SAMI-BB-K9 identification:
Mod Ports Card Type Model Serial No.
--- ----- -------------------------------------- ------------------ -----------
1 2 Supervisor Engine 720 (Active) WS-SUP720-3BXL JAF1226ARQS
2 1 SAMI Module (csgk9) WS-SVC-SAMI-BB-K9 SAD113906P1
4 48 CEF720 48 port 10/100/1000mb Ethernet WS-X6748-GE-TX SAL1127T6XY
Mod MAC addresses Hw Fw Sw Status
--- ---------------------------------- ------ ------------ ------------ -------
1 001e.be6e.a018 to 001e.be6e.a01b 5.6 8.5(2) 12.2(33)SRC5 Ok
2 001d.45f8.f3dc to 001d.45f8.f3e3 2.1 8.7(0.22)FW1 12.4(2010040 Ok
4 001c.587a.ef20 to 001c.587a.ef4f 2.6 12.2(14r)S5 12.2(33)SRC5 Ok
Mod Sub-Module Model Serial Hw Status
---- --------------------------- ------------------ ----------- ------- -------
1 Policy Feature Card 3 WS-F6K-PFC3BXL JAF1226BNQM 1.8 Ok
1 MSFC3 Daughterboard WS-SUP720 JAF1226BNMC 3.1 Ok
2 SAMI Daughterboard 1 SAMI-DC-BB SAD114400L9 1.1 Other
2 SAMI Daughterboard 2 SAMI-DC-BB SAD114207FU 1.1 Other
4 Centralized Forwarding Card WS-F6700-CFC SAL1029VGFK 2.0 Ok
Mod Online Diag Status
After locating the correct slot, issue the "session slot
<module number> processor <3-9>" command to open a console
connection to the respective Cisco Content Services Gateway: Second Generation.
For example: session slot 2 processor 3. The number 3 is the
control processor (CP) number for the CSG2. Always session into CP 3 when
configuring or monitoring the Cisco Content Services Gateway: Second
Generation. Once connected to the Cisco Content Services Gateway: Second
Generation, perform the "show version" command:
The following example shows that the Cisco Content Services
Gateway: Second Generation is running software Release 12.4(24)MD1:
Cisco IOS Software, SAMI Software (SAMI-CSGK9-M), Version 12.4(24)MD1, RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2010 by Cisco Systems, Inc.
Compiled Wed 07-Apr-10 09:50 by prod_rel_team
--- output truncated ---
Content Services Gateway: First Generation is not affected by this
Note: Other SAMI-based applications are not affected. The Cisco Gateway
GPRS Support Node (GGSN), the Cisco Mobile Wireless Home Agent (HA), the Cisco
Wireless Security Gateway (WSG), the Cisco Broadband Wireless Gateway and Cisco
IP Transfer Point (ITP), and the Cisco Long Term Evolution (LTE) Gateway are
The Cisco 7600 Series Router is not affected by this
vulnerability, only the Cisco CSG (2nd generation) module is affected.
No other Cisco products are currently known to be affected
by this vulnerability.
The Cisco Content Services Gateway: Second Generation provides
intelligent network capabilities such as flexible policy management and billing
based on deep-packet inspection, as well as subscriber and application
awareness capabilities that enable mobile operators to quickly and easily offer
value-added, differentiated services over their mobile data networks.
A DoS vulnerability exists in the Cisco Content Services Gateway:
Second Generation could allow an unauthenticated attacker to cause a device
reload by sending crafted ICMP messages to the affected device.
Note: The Cisco Gateway GPRS Support Node (GGSN), the Cisco Mobile Wireless
Home Agent (HA), the Cisco Wireless Security Gateway (WSG), the Cisco Broadband
Wireless Gateway and Cisco IP Transfer Point (ITP), and the Cisco Long Term
Evolution (LTE) Gateway are not affected.
This vulnerability is documented in Cisco bug ID
registered customers only)
and has been assigned
CVE ID CVE-2011-2064.
Cisco has provided scores for the vulnerabilities in this advisory based on the Common Vulnerability Scoring System (CVSS). The CVSS scoring in this Security Advisory is done in accordance with CVSS version 2.0.
CVSS is a standards-based scoring method that conveys vulnerability severity and helps determine urgency and priority of response.
Cisco has provided a base and temporal score. Customers can then compute environmental scores to assist in determining the impact of the vulnerability in individual networks.
Cisco has provided an FAQ to answer additional questions regarding CVSS at
Cisco has also provided a CVSS calculator to help compute the environmental impact for individual networks at
CSCtl79577 - Crafted ICMP Packets may cause CSG2 to reload
Calculate the environmental score of
CVSS Base Score - 7.8
CVSS Temporal Score - 6.4
Successful exploitation of this vulnerability could cause an affected
device to reload. Repeated exploitation could result in a sustained DoS
The Cisco 7600 Series Router is not affected by this vulnerability,
only the Cisco Content Services Gateway: Second Generation module is
When considering software upgrades, also consult
and any subsequent advisories to determine exposure and a complete upgrade
In all cases, customers should exercise caution to be
certain the devices to be upgraded contain sufficient memory and that current
hardware and software configurations will continue to be supported properly by
the new release. If the information is not clear, contact the Cisco Technical
Assistance Center (TAC) or your contracted maintenance provider for assistance.
Each row of the Cisco IOS software table (below) names a
Cisco IOS release train. If a given release train is vulnerable, then the
earliest possible releases that contain the fix (along with the anticipated
date of availability for each, if applicable) are listed in the "First Fixed
Release" column of the table. The "Recommended Release" column indicates the
releases which have fixes for all the published vulnerability at the time of
this Advisory. A device running a release in the given train that is earlier
than the release in a specific column (less than the First Fixed Release) is
known to be vulnerable. Cisco recommends upgrading to a release equal to or
later than the release in the "Recommended Releases" column of the table.
Availability of Repaired Releases
Affected 12.x-Based Releases
First Fixed Release
12.0 - 12.3
12.0 through 12.3 based releases are not affected
Affected 12.4-Based Releases
First Fixed Release
All 12.4MDA releases prior to 12.4(24)MDA5 are affected. First
fixed in 12.4(24)MDA5
Affected 15.X-Based Releases
First Fixed Release
15.0 - 15.1
15.0 through 15.1 based releases are not affected
There are no available workarounds to mitigate this vulnerability other
than applying infrastructure access control lists (iACLs) on the Cisco 7600
router to block ICMP traffic destined to the IP address of the Cisco CSG.
Administrators can construct an iACL by explicitly permitting only authorized
traffic to enter the network at ingress access points or permitting authorized
traffic to transit the network in accordance with existing security policies
and configurations. An iACL workaround cannot provide complete protection
against these vulnerabilities when the attack originates from a trusted source
The iACL policy denies unauthorized ICMP packet types,
including echo request, echo-reply, host-unreachable, traceroute,
packet-too-big, time-exceeded, and unreachable, that are sent to affected
devices. In the following example, 192.168.60.0/24 is the IP address space that
is used by the affected devices, and the host at 192.168.100.1 is considered a
trusted source that requires access to the affected devices. Care should be
taken to allow required traffic for routing and administrative access prior to
denying all unauthorized traffic. Whenever possible, infrastructure address
space should be distinct from the address space used for user and services
segments. Using this addressing methodology will assist with the construction
and deployment of iACLs.
Additional information about iACLs is in
Your Core: Infrastructure Protection Access Control Lists.
ip access-list extended Infrastructure-ACL-Policy
!-- Include explicit permit statements for trusted sources
!-- that require access on the vulnerable protocol
permit icmp host 192.168.100.1 192.168.60.0 0.0.0.255 echo
permit icmp host 192.168.100.1 192.168.60.0 0.0.0.255 echo-reply
permit icmp host 192.168.100.1 192.168.60.0 0.0.0.255 host-unreachable
permit icmp host 192.168.100.1 192.168.60.0 0.0.0.255 traceroute
permit icmp host 192.168.100.1 192.168.60.0 0.0.0.255 packet-too-big
permit icmp host 192.168.100.1 192.168.60.0 0.0.0.255 time-exceeded
permit icmp host 192.168.100.1 192.168.60.0 0.0.0.255 unreachable
!-- The following vulnerability-specific access control entries
!-- (ACEs) can aid in identification of attacks
deny icmp any 192.168.60.0 0.0.0.255 echo
deny icmp any 192.168.60.0 0.0.0.255 echo-reply
deny icmp any 192.168.60.0 0.0.0.255 host-unreachable
deny icmp any 192.168.60.0 0.0.0.255 traceroute
deny icmp any 192.168.60.0 0.0.0.255 packet-too-big
deny icmp any 192.168.60.0 0.0.0.255 time-exceeded
deny icmp any 192.168.60.0 0.0.0.255 unreachable
!-- Explicit deny ACE for traffic sent to addresses configured within
!-- the infrastructure address space
deny ip any 192.168.60.0 0.0.0.255
!-- Permit or deny all other Layer 3 and Layer 4 traffic in accordance
!-- with existing security policies and configurations
!-- Apply iACL to interfaces in the ingress direction
ip access-group Infrastructure-ACL-Policy in
Additional mitigations that can be deployed on Cisco devices within the
network are available in the Cisco Applied Mitigation Bulletin companion
document for this advisory, which is available at the following link:
Cisco has released software updates that address these vulnerabilities. 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.
Customers may only install and expect support for the feature sets they have purchased. By installing, downloading, accessing or otherwise using such software upgrades, customers agree to be bound by the terms of Cisco's software license terms found at http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html
, or as otherwise set forth at Cisco.com Downloads at http://www.cisco.com/public/sw-center/sw-usingswc.shtml
Do not contact firstname.lastname@example.org or email@example.com for software upgrades
Customers with contracts should obtain software through their regular update channels. For most customers, software patches and bug fixes should be obtained through the Software Center on Cisco's worldwide website at http://www.cisco.com
Customers whose Cisco products are provided or maintained through prior or existing agreements with third-party support organizations, such as Cisco Partners, authorized resellers, or service providers should contact that support organization for guidance and assistance with the appropriate course of action in regards to this advisory.
The effectiveness of any workaround or fix is dependent on specific customer situations, such as product mix, network topology, traffic behavior, and organizational mission. Due to the variety of affected products and releases, customers should consult with their service provider or support organization to ensure any applied workaround or fix is the most appropriate for use in the intended network before it is deployed.
Customers who purchase direct from Cisco but do not hold a Cisco
service contract, and customers who purchase through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain software patches and bug fixes by contacting the Cisco Technical Assistance Center (TAC). TAC
contacts are as follows.
+1 800 553 2447 (toll free from within North America)
+1 408 526 7209 (toll call from anywhere in the world)
Customers should have their product serial number available and be
prepared to give the URL of this notice as evidence of entitlement to a software patch or bug fix. Customers without service contracts should request a software patch or bug fix through the TAC.
for additional TAC contact information, including localized telephone numbers,
and instructions and e-mail addresses for use in various languages.
The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability described in this advisory.
This vulnerability was found during internal testing.
THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
A stand-alone copy or Paraphrase of the text of this document that omits the distribution URL in the following section is an uncontrolled copy, and may lack important information or contain factual errors.
This advisory is posted on Cisco's worldwide website at:
In addition to worldwide web posting, a text version of
this notice is clear-signed with the Cisco PSIRT PGP key and is posted to the
following e-mail and Usenet news recipients.
Future updates of this advisory, if any, will be placed on Cisco's
worldwide website, but may or may not be actively announced on mailing lists or
newsgroups. Users concerned about this problem are encouraged to check the
above URL for any updates.
Initial public release.