ID

VAR-200801-0008

CVE

CVE-2008-0028

TITLE

Cisco PIX In IP Interfering with service handling related to packet handling (DoS) Vulnerabilities

DESCRIPTION

Unspecified vulnerability in Cisco PIX 500 Series Security Appliance and 5500 Series Adaptive Security Appliance (ASA) before 7.2(3)6 and 8.0(3), when the Time-to-Live (TTL) decrement feature is enabled, allows remote attackers to cause a denial of service (device reload) via a crafted IP packet. An attacker can exploit this issue to cause the affected devices to reload, denying service to legitimate users. Repeat attacks will result in a prolonged denial-of-service condition. NOTE: The TTL decrement feature is not configured by default on the devices listed above. Devices that do not support the TTL decrement feature are not vulnerable. Common Vulnerabilities and Exposures (CVE) identifier CVE-2008-0028 has been assigned to this vulnerability. Cisco has released free software updates that address this vulnerability. A workaround that mitigates this vulnerability is available. This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20080123-asa.shtml. The ability to decrement the TTL of transient packets can be enabled on a selective or global basis by using the set connection decrement-ttl command in the policy-map class configuration mode. To determine whether you are running this feature use the show running-config command and search for the set connection decrement-ttl command. Alternatively you can use the include argument to search for this command as follows: ASA#show running-config | include decrement-ttl set connection decrement-ttl ASA# The set connection decrement-ttl command is part of a configured class-map. In order for this command to take effect it must be applied using a policy-map (assigned globally or to an interface). The Cisco Firewall Services Module (FWSM) is not vulnerable. No other Cisco products are currently known to be affected by this vulnerability. This vulnerability is documented in Cisco Bug ID CSCsk48199. Vulnerability Scoring Details +---------------------------- Cisco has provided scores for the vulnerability 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. * Cisco PIX and ASA TTL Vulnerability (CSCsk48199) 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 vulnerability described in this advisory will result in a reload of the affected device. Software Versions and Fixes =========================== This vulnerability is fixed in software version 7.2(3)6 or 8.0(3) and later. 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. ASA(config)#policy-map localpolicy1 ASA(config-pmap)#class local_server ASA(config-pmap-c)#no set connection decrement-ttl ASA(config-pmap-c)#exit For additional information on identifying and mitigating TTL based attacks, please refer to the Cisco Applied Intelligence White Paper "TTL Expiry Attack Identification and Mitigation", available at: http://cisco.com/web/about/security/intelligence/ttl-expiry.html Obtaining Fixed Software ======================== Cisco has released free software updates that address this vulnerability. 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. 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. 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-20080123-asa.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-23 | 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. +---------------------------------------------------------------------- All contents are Copyright (C) 2006-2008 Cisco Systems, Inc. All rights reserved. +---------------------------------------------------------------------- Updated: Jan 21, 2008 Document ID: 100314 +---------------------------------------------------------------------- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFHl2u286n/Gc8U/uARAguWAJsHVKpw/9IghAIFi+f6aueoyc8+pQCaAxsH 44Maa1texObtmaCxvo4ucN8= =lT07 -----END PGP SIGNATURE----- . ---------------------------------------------------------------------- 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. This can be exploited to reload an affected device via specially crafted IP packets. SOLUTION: Update to version 7.2(3)6, 8.0(3) or later (please see the vendor's advisory for details). PROVIDED AND/OR DISCOVERED BY: Reported by the vendor. ORIGINAL ADVISORY: http://www.cisco.com/warp/public/707/cisco-sa-20080123-asa.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

AFFECTED PRODUCTS

CVSS

PROBLEMTYPE DATA

THREAT TYPE

remote

TYPE

design error

CONFIGURATIONS

EXPLOIT AVAILABILITY

PATCH

EXTERNAL IDS

REFERENCES

CREDITS

Cisco Security bulletin

SOURCES

LAST UPDATE DATE

2024-11-23T23:00:16.214000+00:00

SOURCES UPDATE DATE

SOURCES RELEASE DATE