ID

VAR-200801-0007

CVE

CVE-2008-0027

TITLE

Cisco Unified Communications Manager (CUCM) and CallManager Heap overflow vulnerability

DESCRIPTION

Heap-based buffer overflow in the Certificate Trust List (CTL) Provider service (CTLProvider.exe) in Cisco Unified Communications Manager (CUCM) 4.2 before 4.2(3)SR3 and 4.3 before 4.3(1)SR1, and CallManager 4.0 and 4.1 before 4.1(3)SR5c, allows remote attackers to cause a denial of service or execute arbitrary code via a long request. Cisco Unified Communications Manager (CUCM) and CallManager Contains a heap overflow vulnerability. Attackers can exploit this issue to execute arbitrary code or to cause denial-of-service conditions. Authentication is not required to exploit this vulnerability. The service operates over a SSL encrypted transport. Due to a logic flaw in the way data is received in a loop a heap allocation can be arbitrarily overflown resulting in the control of subsequent heap chunks. The vulnerability is due to a loop that occurs during receive of socket data. An initial buffer is allocated at 0x19000 bytes, as can bee seen here. .text:00406077 191A8 68+ push 19000h ; size_t .text:0040607C 191AC FF+ call ds:__imp_malloc .text:00406082 191AC 83+ add esp, 10h .text:00406085 1919C 89+ mov [edi+14h], eax .text:00406088 1919C 85+ test eax, eax .text:0040608A 1919C 0F+ jz loc_406238 Once allocated data is read in 0x19000 chunks. If more than 0x4000 bytes of data are left on the socket we loop again as can be seen here. .text:004060A5 191AC FF+ push dword ptr [ebp-14h] ; size_t .text:004060A8 191B0 8D+ lea eax, [ebp-1919Ch] .text:004060AE 191B0 50 push eax ; void * .text:004060AF 191B4 8B+ mov eax, [edi+14h] .text:004060B2 191B4 03+ add eax, [ebp-1Ch] .text:004060B5 191B4 50 push eax ; void * .text:004060B6 191B8 E8+ call memcpy .text:004060B6 191B8 2F+ .text:004060BB 191B8 B8+ mov eax, 16384 .text:004060C0 191B8 83+ add esp, 1Ch .text:004060C3 1919C 39+ cmp [ebp-14h], eax .text:004060C6 1919C 75+ jnz short loc_4060F8 .text:004060C8 1919C 50 push eax ; int .text:004060C9 191A0 68+ push offset str__ErrDExceeds16k ; 'err %d exceeds 16K' .text:004060CE 191A4 8D+ lea eax, [ebp-88h] .text:004060D4 191A4 68+ push 80000h ; int .text:004060D9 191A8 50 push eax ; int .text:004060DA 191AC E8+ call log_message .text:004060DA 191AC B7+ .text:004060DF 191AC 83+ add esp, 10h .text:004060E2 1919C 81+ add dword ptr [ebp-1Ch], 4000h .text:004060E9 1919C 68+ push offset str__MaybeThereIsMoreData__readAgain ; "Maybe there is more data..Read again" .text:004060EE 191A0 68+ push 10000h .text:004060F3 191A4 E9+ jmp loc_405FFF This will continue until heap chunks are overwritten at the users control, which can be exploited to overwrite memory and further lead to arbitrary code execution. -- Vendor Response: http://www.cisco.com/warp/public/707/cisco-sa-20080116-cucmctl.shtml -- Disclosure Timeline: 2007.06.04 - Vulnerability reported to vendor 2008.01.16 - Coordinated public release of advisory -- Credit: This vulnerability was discovered by Cody Pierce - TippingPoint DVLabs. ---------------------------------------------------------------------- A new version (0.9.0.0 - Release Candidate 1) of the free Secunia PSI has been released. The new version includes many new and advanced features, which makes it even easier to stay patched. Successful exploitation allows execution of arbitrary code. CUCM 4.0: Update to a fixed version of CUCM 4.1 or later. CUCM 4.1: Update to CUCM 4.1(3)SR5c, CUCM 4.1(3)SR6, or later. http://www.cisco.com/pcgi-bin/tablebuild.pl/callmgr-41?psrtdcat20e2 CUCM 4.2: Update to CUCM 4.2(3)SR3 or later. http://www.cisco.com/pcgi-bin/tablebuild.pl/callmgr-42?psrtdcat20e2 CUCM 4.3: Update to CUCM 4.3(1)SR1, CUCM 4.3(1)SR1a, or later. http://www.cisco.com/pcgi-bin/tablebuild.pl/callmgr-43?psrtdcat20e2 PROVIDED AND/OR DISCOVERED BY: Cody Pierce, TippingPoint DVLabs ORIGINAL ADVISORY: TPTI-08-02: http://dvlabs.tippingpoint.com/advisory/TPTI-08-02 Cisco (100345): http://www.cisco.com/warp/public/707/cisco-sa-20080116-cucmctl.shtml ---------------------------------------------------------------------- About: This Advisory was delivered by Secunia as a free service to help everybody keeping their systems up to date against the latest vulnerabilities. Subscribe: http://secunia.com/secunia_security_advisories/ Definitions: (Criticality, Where etc.) http://secunia.com/about_secunia_advisories/ Please Note: Secunia recommends that you verify all advisories you receive by clicking the link. Secunia NEVER sends attached files with advisories. Secunia does not advise people to install third party patches, only use those supplied by the vendor. There is a workaround for this vulnerability. Cisco has made free software available to address these vulnerabilities for affected customers. Common Vulnerabilities and Exposures (CVE) identifier CVE-2008-0027 has been assigned to this vulnerability. This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20080116-cucmctl.shtml. CUCM Versions 3.3, 4.0, 4.1 and 5.0 retain the Cisco Unified CallManager name. Products Confirmed Not Vulnerable +-------------------------------- CUCM Versions 3.3, 5.0, 5.1, 6.0, 6.1 and Cisco CallManager Express are not affected by this vulnerability. No other Cisco products are currently known to be affected by this vulnerability. Details ======= Cisco Unified Communications Manager (CUCM) 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, voice-over-IP (VoIP) gateways, and multimedia applications. The CTL contains public keys and other information to allow the Cisco IP Phone devices to establish a trusted relationship with a CUCM server. The CTL is provisioned using the CTL Provider service on a CUCM server and with the CTL Provider client on an administrator workstation. The CTL Provider service needs to be enabled during the initial configuration of a CUCM server /cluster or when changes are required to the CTL. Please consult the Workarounds section of this advisory for information on how to determine if the CTL Provider service is enabled on a CUCM server. The CTL Provider service listens on TCP port 2444 by default, but the port can be modified by the user. This issue is documented in Cisco Bug ID CSCsj22605. 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 CSCsj22605 - CUCM CTL Provider Heap Overflow Vulnerability CVSS Base Score - 10 Access Vector - Network Access Complexity - Low Authentication - None Confidentiality Impact - Complete Integrity Impact - Complete Availability Impact - Complete CVSS Temporal Score - 8.3 Exploitability - Functional Remediation Level - Official-Fix Report Confidence - Confirmed Impact ====== Successful exploitation of this vulnerability may result in a DoS condition or the execution of arbitrary code. 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. Workarounds =========== It is possible to workaround the vulnerability by disabling the CTL Provider service when not in use. Access to the CTL Provider service is required for the initial configuration of the CUCM authentication and encryption features, or during configuration updates. For the CUCM 4.x systems, please consult the following documentation for details on how to disable the CUCM services: http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_administration_guide_chapter09186a008070ec49.html Filtering traffic to the affected CUCM systems on screening devices can be used as a mitigation technique for this vulnerability. To mitigate the CTL Producer service overflow, access to TCP port 2444 should be permitted only between the CUCM servers and administrator workstations running the CTL Provider client. There is currently no supported method to configure filtering directly on a CUCM system. It is possible to change the default ports of the CTL Provider (TCP port 2444) service. If changed, filtering should be based on the port value used. The value of the port can be viewed in CUCM Administration interface by following the System > Service Parameters menu and selecting the CTL Provider service. Filters blocking access to TCP port 2444 should be deployed at the network edge as part of a transit access control list (tACL). Further information about transit access control lists is available in the white paper "Transit Access Control Lists: Filtering at Your Edge," which is available at the following link: http://www.cisco.com/en/US/tech/tk648/tk361/technologies_white_paper09186a00801afc76.shtml Additional mitigations that can be deployed on Cisco devices within the network are available in the Cisco Applied Mitigation Bulletin companion document for this advisory: http://www.cisco.com/warp/public/707/cisco-amb-20080116-cucmctl.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/products/prod_warranties_item09186a008088e31f.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. Fixed software for CUCM can be obtained here: +-------------------------------------------------+ | CUCM | Fixed | Recommended | Download | | Version | Release | Release | Location | |---------+---------+-------------+---------------| | | | Upgrade to | | | CUCM | | a fixed | | | 4.0 | N/A | Version of | N/A | | | | CUCM 4.1 or | | | | | later | | |---------+---------+-------------+---------------| | | | | http:// | | | CUCM | CUCM 4.1(3) | www.cisco.com | | CUCM | 4.1(3) | SR6 or | /pcgi-bin/ | | 4.1 | SR5c | later | tablebuild.pl | | | | | /callmgr-41? | | | | | psrtdcat20e2 | |---------+---------+-------------+---------------| | | | | http:// | | | CUCM | CUCM 4.2(3) | www.cisco.com | | CUCM | 4.2(3) | SR3 or | /pcgi-bin/ | | 4.2 | SR3 | later | tablebuild.pl | | | | | /callmgr-42? | | | | | psrtdcat20e2 | |---------+---------+-------------+---------------| | | | | http:// | | | CUCM | CUCM 4.3(1) | www.cisco.com | | CUCM | 4.3(1) | SR1a or | /pcgi-bin/ | | 4.3 | SR1 | later | tablebuild.pl | | | | | /callmgr-43? | | | | | psrtdcat20e2 | +-------------------------------------------------+ 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/warp/public/687/Directory/DirTAC.shtml 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 TippingPoint. Cisco would like to thank TippingPoint for reporting this vulnerability and working with us towards resolution of this problem. 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-20080116-cucmctl.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-teams@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 | 2008-January-16 | 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----- Version: GnuPG v1.4.8 (Darwin) iEYEARECAAYFAkeOKKYACgkQ86n/Gc8U/uDywwCfVk/A68YckSgZ070lK8aW10By djAAnR/h+tI2S3/7csJyQHrHeZ7Nrhbz =h46X -----END PGP SIGNATURE-----

AFFECTED PRODUCTS

CVSS

PROBLEMTYPE DATA

THREAT TYPE

remote

TYPE

buffer overflow

CONFIGURATIONS

EXPLOIT AVAILABILITY

PATCH

EXTERNAL IDS

REFERENCES

CREDITS

Cody Pierce

SOURCES

LAST UPDATE DATE

2024-11-23T22:24:05.289000+00:00

SOURCES UPDATE DATE

SOURCES RELEASE DATE