[guru] Cisco biztonsagi frissitesek
DATE: Tue, 31 Aug 2010 23:25:48 +0200
A Cisco Unified Communications Manager két DoS hibát is tartalmaz SIP
üzenetek feldolgozása közben.
A Cisco Unified Presence szintén két DoS hibát tartalmaz a SIP üzenetek
feldolgozójában.
A Cisco IOS XR alapú eszközök BGP implementációja hibás, amennyiben a
peer egy érvényes, bár a Cisco által nem ismert attributumot kap, akkor
azt sérülten küldi tovább a többi szomszédes eszköznek, aminek hatására
azok megszakítják a kapcsolatot.
--- Begin Message ---
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Hash: SHA1
Cisco Security Advisory: Cisco Unified Communications Manager Denial
of Service Vulnerabilities
Advisory ID: cisco-sa-20100825-cucm
Revision 1.0
For Public Release 2010 August 25 1600 UTC (GMT)
+---------------------------------------------------------------------
Summary
=======
Cisco Unified Communications Manager contains two denial of service
(DoS) vulnerabilities that affect the processing of Session
Initiation Protocol (SIP) messages. Exploitation of these
vulnerabilities could cause an interruption of voice services.
Cisco has released free software updates that address these
vulnerabilities. There are no workarounds for these vulnerabilities.
This advisory is posted at:
http://www.cisco.com/warp/public/707/cisco-sa-20100825-cucm.shtml
Affected Products
=================
Vulnerable Products
+------------------
The following products are affected by vulnerabilities that are
described in this advisory:
* Cisco Unified Communications Manager 6.x
* Cisco Unified Communications Manager 7.x
* Cisco Unified Communications Manager 8.x
Products Confirmed Not Vulnerable
+--------------------------------
Cisco Unified Communications Manager version 4.x is not affected by
these vulnerabilities. No other Cisco products are currently known to
be affected by these vulnerabilities.
Details
=======
Cisco Unified Communications Manager is the call processing component
of the Cisco IP Telephony solution that extends enterprise telephony
features and functions to packet telephony network devices, such as
IP phones, media processing devices, VoIP gateways, and multimedia
applications.
Cisco Unified Communications Manager contains two DoS vulnerabilities
that involve the processing of SIP messages. Each vulnerability is
triggered by a malformed SIP message that could cause a critical
process to fail, which could result in the disruption of voice
services. All SIP ports (TCP ports 5060 and 5061, UDP ports 5060 and
5061) are affected.
The first SIP DoS vulnerability is documented in Cisco bug ID
CSCtd17310 and has been assigned the CVE identifier CVE-2010-2837.
This vulnerability is fixed in Cisco Unified Communications Manager
versions 6.1(5)SU1, 7.0(2a)SU3, 7.1(3b)SU2, 7.1(5) and 8.0(1). Cisco
Unified Communications Manager version 4.x is not affected.
The second SIP DoS vulnerability is documented in Cisco bug ID
CSCtf66305 and has been assigned the CVE identifier CVE-2010-2838.
The second vulnerability is fixed in Cisco Unified Communications
Manager versions 7.0(2a)SU3, 7.1(5) and 8.0(3). Cisco Unified
Communications Manager versions 4.x and 6.x are not affected.
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
CSCtd17310 - potential core dump issue in SIPStationInit code
CVSS Base Score - 7.8
Access Vector - Network
Access Complexity - Low
Authentication - None
Confidentiality Impact - None
Integrity Impact - None
Availability Impact - Complete
CVSS Temporal Score - 6.4
Exploitability - Functional
Remediation Level - Official-Fix
Report Confidence - Confirmed
CSCtf66305 - CCM Coredump From SendCombinedStatusInfo on
Fuzzed REGISTER Message
CVSS Base Score - 7.8
Access Vector - Network
Access Complexity - Low
Authentication - None
Confidentiality Impact - None
Integrity Impact - None
Availability Impact - Complete
CVSS Temporal Score - 6.4
Exploitability - Functional
Remediation Level - Official-Fix
Report Confidence - Confirmed
Impact
======
Successful exploitation of the vulnerabilities that are described in
this advisory could result in the interruption of voice services.
Cisco Unified Communications Manager will restart the affected
processes, but repeated attacks may result in a sustained 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.
+---------------------------------------+
| Cisco Unified | Recommended |
| Communication Manager | Release |
| Version | |
|-------------------------+-------------|
| 6.x | 6.1(5)SU1 |
|-------------------------+-------------|
| 7.x | 7.1(5b)SU2 |
|-------------------------+-------------|
| 8.x | 8.0(3a) |
+---------------------------------------+
Note: The recommended releases listed in the table above are the
latest Cisco Unified Communications Manager versions available at the
publication of this advisory, and each release includes software
fixes for all the vulnerabilities described in this advisory.
Cisco Unified Communications Manager software can be downloaded at
the following link:
http://tools.cisco.com/support/downloads/go/Redirect.x?mdfid=268439621
Workarounds
===========
There are no workarounds for the vulnerabilities described in this
advisory.
It is possible to mitigate this vulnerability by implementing
filtering on screening devices and permitting access to TCP ports
5060 and 5061 and to UDP ports 5060 and 5061 only from networks that
require SIP access to Cisco Unified Communications Manager servers.
If Cisco Unified Communications Manager does not need to provide SIP
services, administrators can configure the Cisco Unified
Communications Manager to listen for SIP messages on non-standard
ports. Use the following instructions to change the ports from their
default values:
Step 1: Log into the Cisco Unified Communications Manager
Administration web interface.
Step 2: Navigate to System > Cisco Unified CM and locate the
appropriate Cisco Unified Communications Manager.
Step 3: Change the SIP Phone Port and SIP Phone Secure Port fields to
a non-standard port and click Save.
The SIP Phone Port, which is set to 5060 by default, refers to the
TCP and UDP ports on which the Cisco Unified Communications Manager
listens for normal SIP messages. SIP Phone Secure Port, which is set
to 5061 by default, refers to the TCP port on which the Cisco Unified
Communications Manager listens for SIP over Transport Layer Security
(TLS) messages. For additional information about this procedure,
refer to the "Updating a Cisco Unified Communications Manager"
section of the "Cisco Unified Communications Manager Administration
Guide" at:
http://www.cisco.com/en/US/docs/voice_ip_comm/cucmbe/admin/7_0_1/ccmcfg/b02ccm.html#wp1057513
Note: For a SIP port change to take effect, the Cisco CallManager
Service must be restarted. For information on how to restart the
service, refer to the "Restarting the Cisco CallManager Service"
section of the administration guide at:
http://www.cisco.com/en/US/docs/voice_ip_comm/cucmbe/admin/7_0_1/ccmcfg/b03dpi.html#wp1075124
Additional mitigation techniques that can be deployed on Cisco
devices within the network are available in the Cisco Applied
Mitigation Bulletin companion document for this advisory:
http://www.cisco.com/warp/public/707/cisco-amb-20100825-cucm-cup.shtml
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 vulnerabilities described in this advisory.
All vulnerabilities described in this advisory were discovered as a
result of internal testing conducted by Cisco.
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://www.cisco.com/warp/public/707/cisco-sa-20100825-cucm.shtml
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 | | Initial |
| 1.0 | 2010-August-25 | 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/en/US/products/products_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
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Hash: SHA1
Cisco Security Advisory: Cisco Unified Presence Denial of Service
Vulnerabilities
Advisory ID: cisco-sa-20100825-cup
Revision 1.0
For Public Release 2010 August 25 1600 UTC (GMT)
+---------------------------------------------------------------------
Summary
=======
Cisco Unified Presence contains two denial of service (DoS)
vulnerabilities that affect the processing of Session Initiation
Protocol (SIP) messages. Exploitation of these vulnerabilities could
cause an interruption of presence services.
Cisco has released free software updates that address these
vulnerabilities. There are no workarounds for these vulnerabilities.
This advisory is posted at:
http://www.cisco.com/warp/public/707/cisco-sa-20100825-cup.shtml
Affected Products
=================
Vulnerable Products
+------------------
The following products are affected:
* Cisco Unified Presence 6.0 versions prior to 6.0(7)
* Cisco Unified Presence 7.0 versions prior to 7.0(8)
Note: Cisco Unified Presence version 8.0(1) shipped with software
fixes for all the vulnerabilities described in this advisory.
Administrators of systems running Cisco Unified Presence can
determine the software version by viewing the main page of the Cisco
Unified Presence Administration interface. The software version can
be determined by running the command "show version active" using the
command line interface (CLI).
Products Confirmed Not Vulnerable
+--------------------------------
No other Cisco products are currently known to be affected by these
vulnerabilities.
Details
=======
Cisco Unified Presence contains two DoS vulnerabilities that involve
the processing of SIP messages. Each vulnerability is triggered by a
malformed SIP message that could cause a critical process to fail,
which could result in the disruption of presence services. All SIP
ports (TCP ports 5060 and 5061, UDP ports 5060 and 5061) are
affected.
The first SIP DoS vulnerability is documented in Cisco bug ID
CSCtd14474 and has been assigned the CVE identifier CVE-2010-2839.
This vulnerability is fixed in Cisco Unified Presence versions 6.0(7)
and 7.0(8).
The second SIP DoS vulnerability is documented in Cisco bug ID
CSCtd39629 and has been assigned the CVE identifier CVE-2010-2840.
This vulnerability is fixed in Cisco Unified Presence versions 6.0(7)
and 7.0(8).
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
CSCtd14474 - SIPD Coredumps due to Possible Stack Corruption
During Fuzzing
CVSS Base Score - 7.8
Access Vector - Network
Access Complexity - Low
Authentication - None
Confidentiality Impact - None
Integrity Impact - None
Availability Impact - Complete
CVSS Temporal Score - 6.4
Exploitability - Functional
Remediation Level - Official-Fix
Report Confidence - Confirmed
CSCtd39629 - PE Coredump On Subscribe Message with Contact
Field Error
CVSS Base Score - 7.8
Access Vector - Network
Access Complexity - Low
Authentication - None
Confidentiality Impact - None
Integrity Impact - None
Availability Impact - Complete
CVSS Temporal Score - 6.4
Exploitability - Functional
Remediation Level - Official-Fix
Report Confidence - Confirmed
Impact
======
Successful exploitation of any of the vulnerabilities may result in
the interruption of presence services. Cisco Unified Presence will
restart the affected processes, but repeated attacks may result in a
sustained 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.
+---------------------------------------+
| Cisco Unified | Recommended |
| Presence Version | Release |
|-----------------------+---------------|
| 6.0 | 6.0(7) |
|-----------------------+---------------|
| 7.0 | 7.0(8) |
+---------------------------------------+
Cisco Unified Presence software can be downloaded at the following
link:
http://tools.cisco.com/support/downloads/go/Redirect.x?mdfid=280448682
Workarounds
===========
There are no workarounds for the vulnerabilities described in this
advisory.
It is possible to mitigate these vulnerabilities by implementing
filtering on screening devices and permitting access to TCP ports
5060 and 5061 and to UDP ports 5060 and 5061 only from networks that
require SIP access to Cisco Unified Communications Manager servers.
Additional mitigation techniques that can be deployed on Cisco
devices within the network are available in the Cisco Applied
Mitigation Bulletin companion document for this advisory:
http://www.cisco.com/warp/public/707/cisco-amb-20100825-cucm-cup.shtml
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 vulnerabilities described in this advisory.
All vulnerabilities described in this advisory were discovered as a
result of internal testing conducted by Cisco.
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://www.cisco.com/warp/public/707/cisco-sa-20100825-cup.shtml
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 | | Initial |
| 1.0 | 2010-August-25 | 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/en/US/products/products_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
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Cisco Security Advisory: Cisco IOS XR Software Border Gateway
Protocol Vulnerability
Advisory ID: cisco-sa-20100827-bgp
Revision 1.0
For Public Release 2010 August 27 2200 UTC (GMT)
+---------------------------------------------------------------------
Summary
=======
Cisco IOS XR Software contains a vulnerability in the Border Gateway
Protocol (BGP) feature. The vulnerability manifests itself when a BGP
peer announces a prefix with a specific, valid but unrecognized
transitive attribute. On receipt of this prefix, the Cisco IOS XR
device will corrupt the attribute before sending it to the
neighboring devices. Neighboring devices that receive this corrupted
update may reset the BGP peering session.
Affected devices running Cisco IOS XR Software corrupt the
unrecognized attribute before sending to neighboring devices, but
neighboring devices may be running operating systems other than Cisco
IOS XR Software and may still reset the BGP peering session after
receiving the corrupted update. This is per standards defining the
operation of BGP.
Cisco developed a fix that addresses this vulnerability and will be
releasing free software maintenance upgrades (SMU) progressively
starting 28 August 2010. This advisory will be updated accordingly as
fixes become available.
This advisory is posted at:
http://www.cisco.com/warp/public/707/cisco-sa-20100827-bgp.shtml
Affected Products
=================
This vulnerability affects all Cisco IOS XR Software devices
configured with BGP routing.
Vulnerable Products
+------------------
To determine the Cisco IOS XR 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 XR Software by
displaying text similar to "Cisco IOS XR Software". The software
version is displayed after the text "Cisco IOS XR Software".
The following example identifies a Cisco CRS-1 that is running Cisco
IOS XR Software Release 3.6.2:
RP/0/RP0/CPU0:CRS#show version
Tue Aug 18 14:25:17.407 AEST
Cisco IOS XR Software, Version 3.6.2[00]
Copyright (c) 2008 by Cisco Systems, Inc.
ROM: System Bootstrap, Version 1.49(20080319:195807) [CRS-1 ROMMON],
CRS uptime is 4 weeks, 4 days, 1 minute
System image file is "disk0:hfr-os-mbi-3.6.2/mbihfr-rp.vm"
cisco CRS-8/S (7457) processor with 4194304K bytes of memory.
7457 processor at 1197Mhz, Revision 1.2
17 Packet over SONET/SDH network interface(s)
1 DWDM controller(s)
17 SONET/SDH Port controller(s)
8 TenGigabitEthernet/IEEE 802.3 interface(s)
2 Ethernet/IEEE 802.3 interface(s)
1019k bytes of non-volatile configuration memory.
38079M bytes of hard disk.
981440k bytes of ATA PCMCIA card at disk 0 (Sector size 512 bytes).
Configuration register on node 0/0/CPU0 is 0x102
Boot device on node 0/0/CPU0 is mem:
!--- output truncated
The following example identifies a Cisco 12404 router that is running
Cisco IOS XR Software Release 3.7.1:
RP/0/0/CPU0:GSR#show version
Cisco IOS XR Software, Version 3.7.1[00]
Copyright (c) 2008 by Cisco Systems, Inc.
ROM: System Bootstrap, Version 12.0(20051020:160303) SOFTWARE
Copyright (c) 1994-2005 by cisco Systems, Inc.
GSR uptime is 3 weeks, 6 days, 3 hours, 20 minutes
System image file is "disk0:c12k-os-mbi-3.7.1/mbiprp-rp.vm"
cisco 12404/PRP (7457) processor with 2097152K bytes of memory.
7457 processor at 1266Mhz, Revision 1.2
1 Cisco 12000 Series Performance Route Processor
1 Cisco 12000 Series - Multi-Service Blade Controller
1 1 Port ISE Packet Over SONET OC-48c/STM-16 Controller (1 POS)
1 Cisco 12000 Series SPA Interface Processor-601/501/401
3 Ethernet/IEEE 802.3 interface(s)
1 SONET/SDH Port controller(s)
1 Packet over SONET/SDH network interface(s)
4 PLIM QoS controller(s)
8 FastEthernet/IEEE 802.3 interface(s)
1016k bytes of non-volatile configuration memory.
1000496k bytes of disk0: (Sector size 512 bytes).
65536k bytes of Flash internal SIMM (Sector size 256k).
Configuration register on node 0/0/CPU0 is 0x2102
Boot device on node 0/0/CPU0 is disk0:
!--- output truncated
Additional information about Cisco IOS XR Software release naming
conventions is available in the "White Paper: Cisco IOS Reference
Guide" at the following link:
http://www.cisco.com/web/about/security/intelligence/ios-ref.html#9
Additional information about Cisco IOS XR Software time-based release
model is available in the "White Paper: Guidelines for Cisco IOS XR
Software" at the following link:
http://www.cisco.com/en/US/prod/collateral/iosswrel/ps8803/ps5845/product_bulletin_c25-478699.html
BGP is configured in Cisco IOS XR Software with the configuration
command "router bgp [AS Number]" or "router bgp [X.Y]". The device is
vulnerable if it is running an affected Cisco IOS XR Software version
and has BGP configured.
The following example shows a Cisco IOS XR Software device configured
with BGP:
RP/0/0/CPU0:GSR#show running-config | begin router bgp
Building configuration...
router bgp 65535
bgp router-id 192.168.0.1
address-family ipv4 unicast
network 192.168.1.1/32
!
address-family vpnv4 unicast
!
neighbor 192.168.2.1
remote-as 65534
update-source Loopback0
address-family ipv4 unicast
!
!--- output truncated
Products Confirmed Not Vulnerable
+--------------------------------
The following Cisco products are confirmed not vulnerable:
* Cisco IOS Software
* Cisco IOS XR Software not configured for BGP routing
No other Cisco products are currently known to be affected by these
vulnerabilities.
Details
=======
This vulnerability affects Cisco IOS XR devices running affected
software versions and configured with the BGP routing feature.
The vulnerability manifests itself when a BGP peer announces a prefix
with a specific, valid but unrecognized transitive attribute. On
receipt of this prefix, the Cisco IOS XR device will corrupt the
attribute before sending it to the neighboring devices. Neighboring
devices that receive this corrupted update may reset the BGP peering
session.
Affected devices running Cisco IOS XR Software corrupt the
unrecognized attribute before sending to neighboring devices, but
neighboring devices may be running operating systems other than Cisco
IOS XR Software and may still reset the BGP peering session after
receiving the corrupted update. This is per RFC 4271 that defines the
operation of BGP.
After an affected device running Cisco IOS XR Software sends a
corrupted update, it will receive a notification from the neighboring
router and will create a log message like the following example:
bgp[122]: %ROUTING-BGP-5-ADJCHANGE : neighbor 172.16.1.251 Down - BGP Notification received: update malformed
This vulnerability is documented in Cisco Bug ID CSCti62211 and has
been assigned Common Vulnerabilities and Exposures (CVE) ID
CVE-2010-3035.
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
CSCti62211 - BGP flaps due to unknown attribute
CVSS Base Score - 5
Access Vector - Network
Access Complexity - Low
Authentication - None
Confidentiality Impact - None
Integrity Impact - None
Availability Impact - Partial
CVSS Temporal Score - 4.8
Exploitability - Functional
Remediation Level - Unavailable
Report Confidence - Confirmed
Impact
======
Successful exploitation of these vulnerabilities may result in the
continuous resetting of BGP peering sessions. This may lead to
routing inconsistencies and a denial of service for those affected
networks.
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.
+-------------------------------------------------------------------+
| Cisco IOS XR | SMU ID | SMU | Requires |
| Version | | Name | Reload |
|---------------+------------------------------+-------+------------|
| 3.4.0 | Vulnerable; Migrate to 3.4.3 | | |
| | and apply a SMU | | |
|---------------+------------------------------+-------+------------|
| 3.4.1 | SMU will be available on | | |
| | 2010-Sep-9 | | |
|---------------+------------------------------+-------+------------|
| 3.4.2 | SMU will be available on | | |
| | 2010-Sep-9 | | |
|---------------+------------------------------+-------+------------|
| 3.4.3 | SMU will be available on | | |
| | 2010-Sep-5 | | |
|---------------+------------------------------+-------+------------|
| 3.5.2 | SMU will be available on | | |
| | 2010-Sep-5 | | |
|---------------+------------------------------+-------+------------|
| 3.5.3 | SMU will be available on | | |
| | 2010-Sep-9 | | |
|---------------+------------------------------+-------+------------|
| 3.5.4 | SMU will be available on | | |
| | 2010-Sep-5 | | |
|---------------+------------------------------+-------+------------|
| 3.6.0 | SMU will be available on | | |
| | 2010-Sep-9 | | |
|---------------+------------------------------+-------+------------|
| 3.6.1 | SMU will be available on | | |
| | 2010-Sep-3 | | |
|---------------+------------------------------+-------+------------|
| 3.6.2 | SMU will be available on | | |
| | 2010-Aug-30 | | |
|---------------+------------------------------+-------+------------|
| 3.6.3 | SMU will be available on | | |
| | 2010-Sep-3 | | |
|---------------+------------------------------+-------+------------|
| 3.7.0 | SMU will be available on | | |
| | 2010-Sep-9 | | |
|---------------+------------------------------+-------+------------|
| 3.7.1 | SMU will be available on | | |
| | 2010-Sep-1 | | |
|---------------+------------------------------+-------+------------|
| 3.7.2 | SMU will be available on | | |
| | 2010-Sep-3 | | |
|---------------+------------------------------+-------+------------|
| 3.7.3 | SMU will be available on | | |
| | 2010-Sep-3 | | |
|---------------+------------------------------+-------+------------|
| 3.8.0 | SMU will be available on | | |
| | 2010-Sep-3 | | |
|---------------+------------------------------+-------+------------|
| 3.8.1 | SMU will be available on | | |
| | 2010-Sep-3 | | |
|---------------+------------------------------+-------+------------|
| 3.8.2 | SMU will be available on | | |
| | 2010-Aug-30 | | |
|---------------+------------------------------+-------+------------|
| 3.8.3 | SMU will be available on | | |
| | 2010-Sep-1 | | |
|---------------+------------------------------+-------+------------|
| 3.8.4 | SMU will be available on | | |
| | 2010-Aug-28 | | |
|---------------+------------------------------+-------+------------|
| 3.9.0 | SMU will be available on | | |
| | 2010-Sep-1 | | |
|---------------+------------------------------+-------+------------|
| 3.9.1 | SMU will be available on | | |
| | 2010-Aug-28 | | |
+-------------------------------------------------------------------+
Workarounds
===========
There are no workarounds to proactively mitigate this vulnerability.
If a route flap is observed, the prefix with the unrecognized
attribute can be filtered. For further information on filtering on
Cisco IOS XR Software, please consult the document "Implementing
Routing Policy on Cisco IOS XR Software" at the following link:
http://www.cisco.com/en/US/docs/ios_xr_sw/iosxr_r3.0/routing/configuration/guide/rc3rpl.html#wp1118699
Obtaining Fixed Software
========================
Cisco is releasing 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
=====================================
An advertisement of an unrecognized but valid BGP attribute resulted
in resetting of several BGP neighbors on 27 August 2010. This
advertisement was not malicious but inadvertently triggered this
vulnerability.
The Cisco PSIRT is not aware of malicious use of the vulnerability
described in this advisory.
Status of this Notice: INTERIM
==============================
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. CISCO EXPECTS TO UPDATE THIS DOCUMENT AS NEW
INFORMATION BECOMES AVAILABLE.
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://www.cisco.com/warp/public/707/cisco-sa-20100827-bgp.shtml
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 | | Initial |
| 1.0 | 2010-August-27 | 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/en/US/products/products_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
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