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Cisco IOS Software Mobile IP and Mobile IPv6 Vulnerabilities

Advisory ID: cisco-sa-20090325-mobileip

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090325-mobileip

Revision 1.3

For Public Release 2009 March 25 16:00  UTC (GMT)


Summary

Devices that are running Cisco IOS Software and configured for Mobile IP Network Address Translation (NAT) Traversal feature or Mobile IPv6 are vulnerable to a denial of service (DoS) attack that may result in a blocked interface.

Cisco has released free software updates that address these vulnerabilities.

This advisory is posted at the following link http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090325-mobileip.

Note: The March 25, 2009, Cisco IOS Security Advisory bundled publication includes eight Security Advisories. All of the advisories address vulnerabilities in Cisco IOS Software. Each advisory lists the releases that correct the vulnerability or vulnerabilities in the advisory.

Individual publication links are listed below:

Affected Products

Devices that are running an affected version of Cisco IOS Software and configured for Mobile IP NAT Traversal feature or Mobile IPv6 are vulnerable.

Vulnerable Products

Devices running Cisco IOS Software and configured for Mobile IP NAT Traversal feature will have a line similar to the following in the output of the show running-config command:

ip mobile home-agent nat traversal [...]

or

ip mobile foreign-agent nat traversal [...]

or

ip mobile router-service collocated registration nat traversal [...]

Devices running Cisco IOS Software and configured for Mobile IPv6 will have a line similar to the following in the output of the show running-config command:

ipv6 mobile home-agent

To determine the Cisco IOS Software release that is running on a Cisco product, administrators can log in to the device and issue the show version command to display the system banner. The system banner confirms that the device is running Cisco IOS Software by displaying text similar to "Cisco Internetwork Operating System Software" or "Cisco IOS Software." The image name displays in parentheses, followed by "Version" and the Cisco IOS Software release name. Other Cisco devices do not have the show version command or may provide different output.

The following example identifies a Cisco product that is running Cisco IOS Software Release 12.3(26) with an installed image name of C2500-IS-L:

    Router#show version
    Cisco Internetwork Operating System Software
    IOS (tm) 2500 Software (C2500-IS-L), Version 12.3(26), RELEASE SOFTWARE (fc2)
    Technical Support: http://www.cisco.com/techsupport
    Copyright (c) 1986-2008 by cisco Systems, Inc.
    Compiled Mon 17-Mar-08 14:39 by dchih


 !--- output truncated

The following example identifies a Cisco product that is running Cisco IOS Software Release 12.4(20)T with an installed image name of C1841-ADVENTERPRISEK9-M:

    Router#show version
    Cisco IOS Software, 1841 Software (C1841-ADVENTERPRISEK9-M), Version 12.4(20)T, RELEASE SOFTWARE (fc3)
    Technical Support: http://www.cisco.com/techsupport
    Copyright (c) 1986-2008 by Cisco Systems, Inc.
    Compiled Thu 10-Jul-08 20:25 by prod_rel_team


 !--- output truncated

Additional information about Cisco IOS Software release naming conventions is available in "White Paper: Cisco IOS Reference Guide" at the following link: http://www.cisco.com/warp/public/620/1.html.

Products Confirmed Not Vulnerable

Cisco IOS XR is not affected by these vulnerabilities.

Cisco IOS XE is not affected by these vulnerabilities.

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

Details

Mobile IP is part of both IPv4 and IPv6 standards. Mobile IP allows a host device to be identified by a single IP address even though the device may move its physical point of attachment from one network to another. Regardless of movement between different networks, connectivity at the different points is achieved seamlessly without user intervention. Roaming from a wired network to a wireless or wide-area network is also possible.

More information on Mobile IPv6 can be found at the following link: http://www.cisco.com/en/US/docs/ios/ipv6/configuration/guide/ip6-mobile.html

The Mobile IP Support NAT Traversal feature is documented in RFC 3519. It introduces an alternative method for tunneling Mobile IP data traffic. New extensions in the Mobile IP registration request and reply messages have been added for establishing User Datagram Protocol (UDP) tunneling. This feature allows mobile devices in collocated mode that use a private IP address (RFC 1918) or foreign agents (FAs) that use a private IP address for the care-of address (CoA) to establish a tunnel and traverse a NAT-enabled router with mobile node (MN) data traffic from the home agent (HA).

More information on Mobile IP NAT Traversal feature can be found at the following link: http://www.cisco.com/en/US/docs/ios/12_3t/12_3t8/feature/guide/gtnatmip.html

Devices that are running an affected version of Cisco IOS Software and configured for Mobile IPv6 or Mobile IP NAT Traversal feature are affected by a DoS vulnerability. A successful exploitation of this vulnerability could cause an interface to stop processing traffic until the system is restarted. Offending packets need to be destined to the router for a successful exploit.

These vulnerabilities are documented in the Cisco Bug IDs CSCsm97220 ( registered customers only) and CSCso05337 ( registered customers only) and have been assigned Common Vulnerabilities and Exposures (CVE) IDs CVE-2009-0633 and CVE-2009-0634.

Vulnerability Scoring Details

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

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

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

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

CSCsm97220 - Input queue wedged by MIPv6 packets

Calculate the environmental score of CSCsm97220

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

CSCso05337 - HA: Input queue wedged by ICMP packet

Calculate the environmental score of CSCso05337

CVSS Base Score - 7.1

Access Vector

Access Complexity

Authentication

Confidentiality Impact

Integrity Impact

Availability Impact

Network

Medium

None

None

None

Complete

CVSS Temporal Score - 5.9

Exploitability

Remediation Level

Report Confidence

Functional

Official-Fix

Confirmed

Impact

Successful exploitation of the vulnerability may result in an interface to stop processing traffic, causing a DoS condition.

Software Versions and Fixes

When considering software upgrades, also consult http://www.cisco.com/go/psirt and any subsequent advisories to determine exposure and a complete upgrade solution.

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 vulnerabilities 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.

Major Release

Availability of Repaired Releases

Affected 12.0-Based Releases

First Fixed Release

Recommended Release

There are no affected 12.0 based releases

Affected 12.1-Based Releases

First Fixed Release

Recommended Release

There are no affected 12.1 based releases

Affected 12.2-Based Releases

First Fixed Release

Recommended Release

There are no affected 12.2 based releases

Affected 12.3-Based Releases

First Fixed Release

Recommended Release

12.3

Not Vulnerable

 

12.3B

Not Vulnerable

 

12.3BC

Not Vulnerable

 

12.3BW

Not Vulnerable

 

12.3EU

Not Vulnerable

 

12.3JA

Not Vulnerable

 

12.3JEA

Not Vulnerable

 

12.3JEB

Not Vulnerable

 

12.3JEC

Not Vulnerable

 

12.3JK

Not Vulnerable

 

12.3JL

Not Vulnerable

 

12.3JX

Not Vulnerable

 

12.3T

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3TPC

Not Vulnerable

 

12.3VA

Not Vulnerable

 

12.3XA

Not Vulnerable

 

12.3XB

Not Vulnerable

 

12.3XC

Not Vulnerable

 

12.3XD

Not Vulnerable

 

12.3XE

Not Vulnerable

 

12.3XF

Not Vulnerable

 

12.3XG

Not Vulnerable

 

12.3XI

Not Vulnerable

 

12.3XJ

Not Vulnerable

 

12.3XK

Not Vulnerable

 

12.3XL

Not Vulnerable

 

12.3XQ

Not Vulnerable

 

12.3XR

Not Vulnerable

 

12.3XS

Not Vulnerable

 

12.3XU

Not Vulnerable

 

12.3XW

Not Vulnerable

 

12.3XX

Not Vulnerable

 

12.3XY

Not Vulnerable

 

12.3XZ

Not Vulnerable

 

12.3YA

Not Vulnerable

 

12.3YD

Not Vulnerable

 

12.3YF

Not Vulnerable

 

12.3YG

Not Vulnerable

 

12.3YH

Not Vulnerable

 

12.3YI

Not Vulnerable

 

12.3YJ

Not Vulnerable

 

12.3YK

Releases prior to 12.3(11)YK3 are vulnerable, release 12.3(11)YK3 and later are not vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YM

12.3(14)YM13

12.3(14)YM13

12.3YQ

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YS

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YT

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YU

Vulnerable; migrate to 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.3YX

Releases prior to 12.3(14)YX10 are vulnerable, release 12.3(14)YX10 and later are not vulnerable;

12.3(14)YX14

12.3YZ

Not Vulnerable

 

12.3ZA

Not Vulnerable

 

Affected 12.4-Based Releases

First Fixed Release

Recommended Release

12.4

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.4(18e)

12.4(23a); Available on 05-JUN-2009

12.4JA

Not Vulnerable

 

12.4JDA

Not Vulnerable

 

12.4JK

Not Vulnerable

 

12.4JL

Not Vulnerable

 

12.4JMA

Not Vulnerable

 

12.4JMB

Not Vulnerable

 

12.4JX

Not Vulnerable

 

12.4MD

Not Vulnerable

 

12.4MR

12.4(19)MR

12.4(19)MR2

12.4SW

Not Vulnerable

 

12.4T

12.4(20)T

12.4(15)T8

12.4(15)T9; Available on 29-APR-2009

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XA

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XB

12.4(15)T8

12.4(20)T

12.4(15)T9; Available on 29-APR-2009

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XC

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XD

12.4(4)XD12; Available on 27-MAR-2009

12.4(4)XD12; Available on 27-MAR-2009

12.4XE

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XF

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XG

Not Vulnerable

 

12.4XJ

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XK

Not Vulnerable

 

12.4XL

12.4(15)XL4

12.4(15)XL4

12.4XM

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XN

Vulnerable; contact TAC

 

12.4XP

Vulnerable; contact TAC

 

12.4XQ

12.4(15)XQ2

12.4(15)XQ2

12.4XR

12.4(15)XR4

12.4(22)T1

12.4XT

Vulnerable; first fixed in 12.4T

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XV

Vulnerable; contact TAC

 

12.4XW

12.4(11)XW10

12.4(11)XW10

12.4XY

12.4(15)XY4

12.4(22)T1

12.4(15)T9; Available on 29-APR-2009

12.4XZ

12.4(15)XZ1

12.4(15)XZ2

12.4YA

Not Vulnerable

 

12.4YB

Not Vulnerable

 

12.4YD

Not Vulnerable

 

Workarounds

The following mitigation and identification methods have been identified for these vulnerabilities:

Infrastructure Access Control Lists

Although it is often difficult to block traffic that transits a network, it is possible to identify traffic that should never be allowed to target infrastructure devices and block that traffic at the border of networks. Infrastructure Access Control Lists (iACLs) are a network security best practice and should be considered as a long-term addition to good network security as well as a workaround for these specific vulnerabilities. The iACL example below should be included as part of the deployed infrastructure access-list which will protect all devices with IP addresses in the infrastructure IP address range:

IPv4 example:


!--- Anti-spoofing entries are shown here. !--- Deny special-use address sources. !--- Refer to RFC 3330 for additional special use addresses. 

access-list 110 deny ip host 0.0.0.0 any
access-list 110 deny ip 127.0.0.0 0.255.255.255 any
access-list 110 deny ip 192.0.2.0 0.0.0.255 any
access-list 110 deny ip 224.0.0.0 31.255.255.255 any


!--- Filter RFC 1918 space.


access-list 110 deny ip 10.0.0.0 0.255.255.255 any
access-list 110 deny ip 172.16.0.0 0.15.255.255 any
access-list 110 deny ip 192.168.0.0 0.0.255.255 any


!--- Deny your space as source from entering your AS. !--- Deploy only at the AS edge.



access-list 110 deny ip YOUR_CIDR_BLOCK any


!--- Permit BGP.


access-list 110 permit tcp host bgp_peer host router_ip eq bgp 
access-list 110 permit tcp host bgp_peer eq bgp host router_ip


!--- Deny access to internal infrastructure addresses.


access-list 110 deny ip any INTERNAL_INFRASTRUCTURE_ADDRESSES


!--- Permit transit traffic.


access-list 110 permit ip any any

IPv6 example:


!--- Configure the access-list.


ipv6 access-list iacl


!--- Deny your space as source from entering your AS. !--- Deploy only at the AS edge.


 deny ipv6 YOUR_CIDR_BLOCK_IPV6 any


!--- Permit multiprotocol BGP.


 permit tcp host bgp_peer_ipv6 host router_ipv6 eq bgp
 permit tcp host bgp_peer_ipv6 eq bgp host router_ipv6


!--- Deny access to internal infrastructure addresses.

 
deny ipv6 any INTERNAL_INFRASTRUCTURE_ADDRESSES_IPV6


!--- Permit transit traffic.


 permit ipv6 any any

The white paper entitled "Protecting Your Core: Infrastructure Protection Access Control Lists" presents guidelines and recommended deployment techniques for infrastructure protection access lists. This white paper can be obtained at the following link http://www.cisco.com/en/US/tech/tk648/tk361/technologies_white_paper09186a00801a1a55.shtml

Cisco IOS Embedded Event Manager

It is possible to detect blocked interface queues with a Cisco IOS Embedded Event Manager (EEM) policy. EEM provides event detection and reaction capabilities on a Cisco IOS device. EEM can alert administrators of blocked interfaces with email, a syslog message, or a Simple Network Management Protocol (SNMP) trap.

A sample EEM policy that uses syslog to alert administrators of blocked interfaces is available at Cisco Beyond, an online community dedicated to EEM. A sample script is available at the following link:

http://forums.cisco.com/eforum/servlet/EEM?page=eem&fn=script&scriptId=981

More information about EEM is available from Cisco.com at the following link: http://www.cisco.com/en/US/products/ps6815/products_ios_protocol_group_home.html

Obtaining Fixed Software

Cisco has released free 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 psirt@cisco.com or security-alert@cisco.com for software upgrades.

Customers with Service Contracts

Customers with contracts should obtain upgraded software through their regular update channels. For most customers, this means that upgrades should be obtained through the Software Center on Cisco's worldwide website at http://www.cisco.com.

Customers using Third Party Support Organizations

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 without Service Contracts

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 acquire upgrades 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)
  • e-mail: tac@cisco.com

Customers should have their product serial number available and be prepared to give the URL of this notice as evidence of entitlement to a free upgrade. Free upgrades for non-contract customers must be requested through the TAC.

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

Exploitation and Public Announcements

The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability described in this advisory.

This vulnerability was reported to Cisco by a customer.

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's worldwide website at :

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090325-mobileip

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.

  • 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
  • comp.dcom.sys.cisco@newsgate.cisco.com

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.


Revision History

Revision 1.3

2009-June-25

Removed references to the March/09 combined fixed software table.

Revision 1.2

2009-June-1

Updated expected public availability date for release 12.4(23a).

Revision 1.1

2009-May-1

Updated expected public availability date for release 12.4(23a).

Revision 1.0

2009-Mar-25

Initial public release

Cisco Security Procedures

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