-----BEGIN PGP SIGNED MESSAGE----- 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 -----BEGIN PGP SIGNATURE----- iD8DBQFMdTQQ86n/Gc8U/uARApXmAJ9y90DCyAqXTXRM2tutg4b7i2Xl9gCfe+pa +dZWj+EDOmZ+50IcJlI1q58= =H2k/ -----END PGP SIGNATURE-----