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Multiple Vulnerabilities in Cisco NX-OS-Based Products

Advisory ID: cisco-sa-20130424-nxosmulti

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130424-nxosmulti

Revision 1.2

Last Updated  2013 April 26 19:40  UTC (GMT)

For Public Release 2013 April 24 16:00  UTC (GMT)


Summary

Cisco Nexus, Cisco Unified Computing System (UCS), Cisco MDS 9000 Series Multilayer Switches, and Cisco 1000 Series Connected Grid Routers (CGR) are all based on the Cisco NX-OS operating system.  These products are affected by one or more of the following vulnerabilities:

  • Multiple Cisco Discovery Protocol Vulnerabilities in Cisco NX-OS-Based Products
  • Cisco NX-OS Software SNMP and License Manager Buffer Overflow Vulnerability
  • Cisco NX-OS Software SNMP Buffer Overflow Vulnerability
  • Cisco NX-OS Software Jumbo Packet Denial of Service Vulnerability

Cisco has released free software updates that address these vulnerabilities.

This advisory is available at the following link:
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130424-nxosmulti

Affected Products

Cisco products running or based on the Cisco NX-OS Software high-speed routing and switching platform are affected by one or more of the vulnerabilities detailed in this advisory.

Vulnerable Products

The following products are vulnerable:

Cisco UCS 6100 = Cisco Unified Computing Server Fabric Interconnect 6100 Series devices
Cisco UCS 6200 = Cisco Unified Computing Server Fabric Interconnect 6200 Series devices
Cisco Nexus 7000 = Cisco Nexus 7000 Series devices
Cisco Nexus 5000 = Cisco Nexus 5010 and Cisco Nexus 5020 devices
Cisco Nexus 5500 = Cisco Nexus 5500 Series devices
Cisco Nexus 4000 = Cisco Nexus 4000 Series blade devices
Cisco Nexus 3000 = Cisco Nexus 3000 Series devices
Cisco Nexus 1000v = Cisco Nexus 1000v virtual switches and 1010 Virtual Service Appliances
Cisco MDS 9000 = Cisco MDS 9000 Multilayer Switch/Director Family devices
Cisco CGR 1000 = Cisco Connected Grid Router 1000 Series devices

The following table details which products are affected by each vulnerability:

Cisco Nexus 7000 Cisco Nexus 5000
Cisco Nexus 5500 Cisco Nexus 4000 Cisco Nexus 3000 Cisco Nexus 1000V Cisco MDS 9000 Cisco UCS 6100
 Cisco UCS 6200
Cisco CGR 1000
Multiple CDP
Buffer Overflow
CVE-2013-1178
X
X
X X X X X X  X X
SNMP & License Manager
Buffer Overflow
CVE-2013-1179
X




 X
 
SNMP Buffer Overflow
CVE-2013-1180
X




 X
 
Jumbo Frame
Denial of Service
CVE-2013-1181
 
X
X


 
 X
 Recommended Software
5.2(9)/6.1(1)
5.2(1)N1(4)
5.2(1)N1(4) 4.1(2)E1(1j) 5.0(3)U5(1e) 4.2(1)SV2(1.1) 5.2(8)
2.1.1e
2.1.1e
CG4(1)

Note: The recommended software releases above resolve all issues impacting each platform in the preceding table.

Products Confirmed Not Vulnerable

The Cisco Nexus 3548 Switch is not affected by the vulnerabilities described in this document.

The Cisco Nexus 6000 Series of devices is not affected by the vulnerabilities described in this document.

No other Cisco products are currently known to be affected by these vulnerabilities.

Details

Multiple Cisco Discovery Protocol Vulnerabilities in Cisco NX-OS-Based Products

Cisco NX-OS based devices contain multiple buffer overflow vulnerabilities in Cisco Discovery Protocol (CDP) subsystem. These vulnerabilities could allow an unauthenticated, adjacent attacker to execute arbitrary code with elevated privileges. The vulnerabilities are due to a failure to properly handle malformed Cisco Discovery Protocol packets. An attacker could exploit these vulnerabilities by passing malformed Cisco Discovery Protocol packets to an affected device. Successful exploitation of these vulnerabilities could allow the attacker to execute arbitrary code with elevated privileges.

Because Cisco Discovery Protocol works at the data link layer (Layer 2), an attacker must be able to submit an Ethernet frame directly to an affected device to exploit this vulnerability. This action may be possible in situations where the affected system is part of a bridged network or connected to an unpartitioned device, such as a network hub.

This vulnerability is documented in the following Cisco bug IDs, and has been assigned Common Vulnerabilities and Exposures (CVE) ID CVE-2013-1178.

Cisco Bug IDs:

Cisco NX-OS Software SNMP and License Manager Buffer Overflow Vulnerability

Cisco NX-OS Software-based devices contain a buffer overflow vulnerability in the SNMP subsystem. An authenticated, remote attacker can exploit the vulnerability by submitting a malicious SNMP query via UDP port 161 to trigger a buffer overflow condition in the SNMP and License Manager components of the device. Successful exploitation could allow the attacker to execute arbitrary code with elevated privileges.

SNMP is disabled by default and must be explicitly configured by an administrator. Because SNMP is primarily a UDP-based protocol, no TCP three-way handshake is required to exploit this vulnerability, and the malicious request could contain a spoofed origin. The attacker must know the configured community strings for SNMP version 1 and version 2. Exploitation also requires a valid username and password when a device is configured for SNMP version 3.

This vulnerability can be triggered via SNMP over IPv4 and SNMP over IPv6.

This vulnerability is documented by Cisco bug ID CSCtx54830 (registered customers only) and has been assigned CVE ID CVE-2013-1179.

Cisco NX-OS Software SNMP Buffer Overflow Vulnerability

Cisco NX-OS based devices contain a buffer overflow vulnerability in the SNMP subsystem.  An authenticated, remote attacker who can submit a malicious SNMP query via UDP port 161 could exploit the vulnerability to trigger a buffer overflow condition in the SNMP component of the device.  Successful exploitation could allow the attacker to execute arbitrary code with elevated privileges. 

SNMP is disabled by default, and must be explicitly configured by an administrator.  Because SNMP is primarily a UDP based protocol, no TCP three-way handshake is required to exploit this vulnerability, and the malicious request could contain a spoofed origin.  The attacker must know the configured community strings for SNMP version 1 and version 2.  Exploitation also requires a valid username and password when a device is configured for SNMP version 3.

This vulnerability can be triggered via SNMP over IPv4 and SNMP over IPv6.

This vulnerability is documented by Cisco bug ID CSCtx54822 (registered customers only) and has been assigned CVE ID CVE-2013-1180.

Cisco NX-OS Software Jumbo Packet Denial of Service Vulnerability

Cisco NX-OS based devices contain a denial of service (DoS) vulnerability.  An unauthenticated, remote attacker who can send a jumbo frame packet to the management interface of an affected device could cause the device to crash and reload.

The vulnerability is due to improper input validation of jumbo packets.  Large packets that are sent through the switching fabric of the device will not trigger the vulnerability.


This vulnerability is documented in the following Cisco bug IDs, and has been assigned Common Vulnerabilities and Exposures (CVE) ID CVE-2013-1181.

Cisco Bug IDs:

Vulnerability Scoring Details

Cisco has scored the vulnerabilities in this advisory based on the Common Vulnerability Scoring System (CVSS). The CVSS scoring in this security advisory is in accordance with CVSS version 2.0.

CVSS is a standards-based scoring method that conveys vulnerability severity and helps organizations determine the urgency and priority of a response.

Cisco has provided a base and temporal score. Customers can also compute environmental scores that help determine the impact of the vulnerability in their own networks.

Cisco has provided additional information regarding CVSS at the following link:

http://www.cisco.com/web/about/security/intelligence/cvss-qandas.html

Cisco has also provided a CVSS calculator to compute the environmental impact for individual networks at the following link:


http://intellishield.cisco.com/security/alertmanager/cvss


CSCtu10630, CSCtu10551, CSCtu10550, CSCtu10548, CSCtu10544, CSCtw56581, CSCuf61275 - Multiple Cisco Discovery Protocol Vulnerabilities in Cisco NX-OS-Based Products

Calculate the environmental score of CSCtu10630

CVSS Base Score - 8.3

Access Vector

Access Complexity

Authentication

Confidentiality Impact

Integrity Impact

Availability Impact

Adjacent Network

Low

None

Complete

Complete

Complete

CVSS Temporal Score - 6.9

Exploitability

Remediation Level

Report Confidence

Functional

Official-Fix

Confirmed




CSCtx54830 - Cisco NX-OS Software SNMP and License Manager Buffer Overflow Vulnerability

Calculate the environmental score of CSCtx54830

CVSS Base Score - 9.0

Access Vector

Access Complexity

Authentication

Confidentiality Impact

Integrity Impact

Availability Impact

Network

Low

Single

Complete

Complete

Complete

CVSS Temporal Score - 7.4

Exploitability

Remediation Level

Report Confidence

Functional

Official-Fix

Confirmed




CSCtx54822 - Cisco NX-OS Software SNMP Buffer Overflow Vulnerability

Calculate the environmental score of CSCtx54822

CVSS Base Score - 9.0

Access Vector

Access Complexity

Authentication

Confidentiality Impact

Integrity Impact

Availability Impact

Network

Low

Single

Complete

Complete

Complete

CVSS Temporal Score - 7.4

Exploitability

Remediation Level

Report Confidence

Functional

Official-Fix

Confirmed




CSCts10593, CSCtx95389, CSCtx17544 - Cisco NX-OS Software Jumbo Packet Denial of Service Vulnerability

Calculate the environmental score of CSCts10593

CVSS Base Score - 7.8

Access Vector

Access Complexity

Authentication

Confidentiality Impact

Integrity Impact

Availability Impact

Network

Low

None

None

None

Complete

CVSS Temporal Score - 6.4

Exploitability

Remediation Level

Report Confidence

Functional

Official-Fix

Confirmed

Impact

Successful exploitation of any of the Cisco Discovery Protocol vulnerabilities detailed in this document could allow an unauthenticated, adjacent attacker to execute arbitrary code with elevated privileges.

Successful exploitation of either of the SNMP vulnerabilities could allow an attacker to execute arbitrary code with elevated privileges, which could lead to a complete compromise of an affected device.

Successful exploitation of the jumbo packet vulnerability could allow an attacker to cause a device to restart. A sustained attack could result in an extended DoS condition.

Software Versions and Fixes

When considering software upgrades, customers are advised to consult the Cisco Security Advisories and Responses archive at http://www.cisco.com/go/psirt and review subsequent advisories to determine exposure and a complete upgrade solution.

In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.


Nexus 7000

Affected First Fixed Recommended
Multiple CDP
CVE-2013-1178
4.1(x)
4.2(x)
5.0(x)
5.1(x)
5.2(3a) and Prior
6.0(x)
5.2(4)
6.1(1)
5.2(9)
6.1(1)
SNMP & License Manager
CVE-2013-1179
4.1(x)
4.2(x)
5.0(x)
5.1(x)
5.2(4) and Prior
6.0(x)
5.2(5)
6.1(1)
5.2(9)
6.1(1)
SNMP
CVE-2013-1180
4.1(x)
4.2(x)
5.0(x)
5.1(x)
5.2(4) and Prior
6.0(x)
5.2(5)
6.1(1)
5.2(9)
6.1(1)

Nexus 5000/Nexus 5500

Affected First Fixed Recommended
Multiple CDP
CVE-2013-1178
4.0(x)
4.1(x)
4.2(x)
5.0(x)
5.1(3)N1(1)
5.2(1)N1(4)
Jumbo Frame - Nexus 5500
CVE-2013-1181
4.0(x)
4.1(x)
4.2(x)
5.0(3)N2(1) and Prior
5.0(3)N2(2)
5.2(1)N1(4)

Nexus 4000

Affected First Fixed Recommended
Multiple CDP
CVE-2013-1178
4.1(2)E1(1g) and Prior
4.1(2)E1(1h)
4.1(2)E1(1j)

Nexus 3000

Affected First Fixed Recommended
Multiple CDP
CVE-2013-1178
5.0(3)U1(1x)
5.0(3)U1(2x)
5.0(3)U2(1)
5.0(3)U2(2x)
5.0(3)U3(1)
5.0(3)U5(1e)
Jumbo Frame
CVE-2013-1181
5.0(3)U1(1x)
5.0(3)U1(2x)
5.0(3)U2(1)
5.0(3)U2(2x)
5.0(3)U3(1)
5.0(3)U3(2)
5.0(3)U5(1e)

Nexus 1000V

Affected First Fixed Recommended
Multiple CDP
CVE-2013-1178
4.0(x)
4.2(1)SV1(4b) and Prior
4.2(1)SV1(5.1)
4.2(1)SV2(1.1)

MDS 9000

Affected First Fixed Recommended
Multiple CDP
CVE-2013-1178
4.1(x)
4.2(x)
5.0(x)
5.2(3) and Prior
5.2(4)
5.2(8)
SNMP & License Manager
CVE-2013-1179
4.1(x)
4.2(x)
5.0(x)
5.2(4) and Prior
5.2(5)
5.2(8)
SNMP
CVE-2013-1180
4.1(x)
4.2(x)
5.0(x)
5.2(4) and Prior
5.2(5)
5.2(8)

Unified Computing System

Affected First Fixed Recommended
Multiple CDP
CVE-2013-1178
1.0(x)
1.1(x)
1.2(x)
1.3(x)
1.4(x)
2.0(1x) and Prior
2.0(2m)
2.1(1a)
2.1.1e
Jumbo Frame - UCS 6200
CVE-2013-1181
1.0(x)
1.1(x)
1.2(x)
1.3(x)
1.4(x)
2.0(1t) and prior
2.0(1w)
2.1.1e

Connected Grid Router 1000 Series

Affected First Fixed Recommended
Multiple CDP
CVE-2013-1178
CG1(4)
CG1(5)
CG3(1)
CG3(2)
CG3(3)
CG4(1)
CG4(1)

Workarounds

No on-device workarounds exist for any of the vulnerabilities detailed in this advisory.

Cisco has released an Applied Mitigation Bulletin (AMB) that explains how to detect and mitigate potential exploitation of these vulnerabilities. The AMB Identifying and Mitigating Exploitation of Multiple Vulnerabilities in Cisco NX-OS-Based Products is available at:
http://tools.cisco.com/security/center/viewAMBAlert.x?alertId=28737

Obtaining Fixed Software

Cisco has released free software updates that address the vulnerabilities described in this advisory. Prior to deploying software, customers are advised to consult their maintenance providers or check the software for feature set compatibility and known issues that are specific to their environments.

Customers may only install and expect support for feature sets they have purchased. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license at http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html.

Customers with Service Contracts

Customers with contracts should obtain upgraded software through their regular update channels. For most customers, upgrades should be obtained through the Software Navigator on Cisco.com at http://www.cisco.com/cisco/software/navigator.html.

Customers using Third Party Support Organizations

Customers with Cisco products that 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 organization for assistance with the appropriate course of action.

The effectiveness of any workaround or fix depends on specific customer situations, such as product mix, network topology, traffic behavior, and organizational mission. Because of the variety of affected products and releases, customers should consult their service providers or support organizations to ensure that any applied workaround or fix is the most appropriate in the intended network before it is deployed.

Customers without Service Contracts

Customers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco Technical Assistance Center (TAC):
  • +1 800 553 2447 (toll free from within North America)
  • +1 408 526 7209 (toll call from anywhere in the world)
  • e-mail: tac@cisco.com
Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade. Customers without service contracts should request free upgrades through the TAC.

Refer to Cisco Worldwide Contacts at http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html for additional TAC contact information, including localized telephone numbers, instructions, and e-mail addresses for support in various languages.

Exploitation and Public Announcements

The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.

The following vulnerabilities were discovered during an internal security evaluation of NX-OS based products:
  • Multiple Cisco Discovery Protocol Vulnerabilities in Cisco NX-OS-Based Products
  • Cisco NX-OS Software SNMP and License Manager Buffer Overflow Vulnerability
  • Cisco NX-OS Software SNMP Buffer Overflow Vulnerability
The Cisco NX-OS Software Jumbo Packet Denial of Service Vulnerability was identified by the Cisco TAC while assisting customers.

Status of this Notice: Final

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.


Distribution

This advisory is posted on Cisco Security at the following link:

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130424-nxosmulti

Additionally, a text version of this advisory is clear signed with the Cisco PSIRT PGP key and circulated among the following e-mail addresses:
  • cust-security-announce@cisco.com
  • first-bulletins@lists.first.org
  • bugtraq@securityfocus.com
  • vulnwatch@vulnwatch.org
  • cisco@spot.colorado.edu
  • cisco-nsp@puck.nether.net
  • full-disclosure@lists.grok.org.uk
Future updates of this advisory, if any, will reside on Cisco.com but may not be announced on mailing lists. Users can monitor this advisory's URL for any updates.

Revision History

Revision 1.2 2013-April-26 Updated summary table in Affected Products for clarification. Corrected UCS 6100/6200 information for jumbo frame vulnerability in summary table.
Revision 1.1 2013-April-24 Clarified affected platforms for certain vulnerabilities.
Revision 1.0 2013-April-24 Initial public release.

Cisco Security Procedures

Complete information about reporting security vulnerabilities in Cisco products, obtaining assistance with security incidents, and registering to receive security information from Cisco is available on Cisco.com at http://www.cisco.com/web/about/security/psirt/security_vulnerability_policy.html. This web page includes instructions for press inquiries regarding Cisco Security Advisories. All Cisco Security Advisories are available at http://www.cisco.com/go/psirt.