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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2006.0178 -- [Cisco] Cisco response to multiple PIX DoS vulnerabilities 9 March 2006 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Cisco PIX 7.0 Cisco PIX 6.3 Publisher: Cisco Systems Operating System: Cisco Impact: Denial of Service Access: Remote/Unauthenticated Ref: ESB-2005.0935 - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Cisco Response ============== This is Cisco PSIRT's response to the statements made by Arhont Ltd.- Information Security in their messages: "[Full-disclosure] Cisco PIX embryonic state machine TTL(n-1) DoS" and "[Full-disclosure] Cisco PIX embryonic state machine 1b data DoS" both posted on March 7, 2006. The original emails are available at: http://lists.grok.org.uk/pipermail/full-disclosure/2006-March/042771.html and http://lists.grok.org.uk/pipermail/full-disclosure/2006-March/042772.html These issues have the same root cause that was documented in Arhont Ltd.- Information Security's message: "[Full-disclosure] Cisco PIX TCP Connection Prevention", posted on November 22, 2005 at: http://lists.grok.org.uk/pipermail/full-disclosure/2005-November/038971.html As detailed in our reply also dated November 22, 2005, this issue is being tracked by two Cisco Bug ID's: * CSCsc14915 -- PIX 6.3 Spoofed TCP SYN packets can block legitimate TCP connections This Bug ID tracks the issue for PIX software version 6.3 and older. This DDTS is resolved and available in PIX software version 6.3(5.106). There are workarounds available to mitigate the issue. * CSCsc16014 -- PIX 7.0 Spoofed TCP SYN packets can block legitimate TCP connections This Bug ID tracks the issue for PIX/ASA software version 7.0. This DDTS is resolved and available in PIX/ASA software versions 7.0(4.005) and 7.1(1). Additional mitigations and workarounds exist to limit or eliminate the issue. Our November 22, 2005 reply is available at: http://www.cisco.com/warp/public/707/cisco-response-20051122-pix.shtml We would like to thank Arhont Ltd.- Information Security for ensuring that these issues were previously addressed as well. We greatly appreciate the opportunity to work with researchers on security vulnerabilities, and welcome the opportunity to review and assist in product reports. Additional Information ====================== There have been updates to the information available for these two Bug ID's since November 22, 2005. The updated Release Note Enclosures are available at: CSCsc14915 -- PIX 6.3 Spoofed TCP SYN packets can block legitimate TCP connections http://www.cisco.com/pcgi-bin/Support/Bugtool/onebug.pl?bugid=CSCsc14915 (registered customers only: http://tools.cisco.com/RPF/register/register.do) CSCsc16014 -- PIX 7.0 Spoofed TCP SYN packets can block legitimate TCP connections http://www.cisco.com/pcgi-bin/Support/Bugtool/onebug.pl?bugid=CSCsc16014 (registered customers only: http://tools.cisco.com/RPF/register/register.do) 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 v1.4.0 (SunOS) iD8DBQFEDd6A8NUAbBmDaxQRAgWkAKCYadpRWwbuNfz7CyihaGqO2cGBegCgo2tg onXhkGjRvA2eEd3tlKCTER4= =FSMY - -----END PGP SIGNATURE----- - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. 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Previous advisories and external security bulletins can be retrieved from: http://www.auscert.org.au/render.html?cid=1980 If you believe that your computer system has been compromised or attacked in any way, we encourage you to let us know by completing the secure National IT Incident Reporting Form at: http://www.auscert.org.au/render.html?it=3192 =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQCVAwUBRA+PZSh9+71yA2DNAQJqrQP+OGiku31QKrLAIOM7kC+Qz+ZpTfEDV2Fr UiFHEns7T0HJN1yRN/IxbMNcHnsBfuXiyIElhd8uP55/yRjQ7mEX7CyeEecP4Zy5 t5bDXQnqvJZYSYf3QFxiDZn9Wa/qvhINXCY8sUZCCt7RfrkhZQaifpd0buc4ZCYm m2yv5kNZBfs= =HuU0 -----END PGP SIGNATURE-----