====================================================================== Secunia Research 31/07/2008 - Blue Coat K9 Web Protection "Referer" Header Buffer Overflow - ====================================================================== Table of Contents Affected Software....................................................1 Severity.............................................................2 Vendor's Description of Software.....................................3 Description of Vulnerability.........................................4 Solution.............................................................5 Time Table...........................................................6 Credits..............................................................7 References...........................................................8 About Secunia........................................................9 Verification........................................................10 ====================================================================== 1) Affected Software * Blue Coat K9 Web Protection 3.2.44 with Filter version 3.2.32. NOTE: Other versions may also be affected. ====================================================================== 2) Severity Rating: Highly critical Impact: System compromise Where: Remote ====================================================================== 3) Vendor's Description of Software "K9 Web Protection is our free Internet filtering and control solution for the home. K9 puts YOU in control of the Internet so you can protect your kids.". Product Link: http://www.k9webprotection.com/ ====================================================================== 4) Description of Vulnerability Secunia Research has discovered a vulnerability in K9 Web Protection, which can be exploited by malicious people to compromise a user's system. The vulnerability is caused by a boundary error in the filter service (k9filter.exe) during processing of "Referer" headers when the web-based K9 Web Protection Administration interface is accessed. This can be exploited to cause a stack-based buffer overflow via an overly long "Referer:" header. Successful exploitation allows execution of arbitrary code when a user e.g. visits a malicious web site. ====================================================================== 5) Solution The vendor is reportedly working on a fixed version, which may be available shortly. ====================================================================== 6) Time Table 29/06/2007 - Vendor notified via e-mail. 03/07/2007 - Vendor notified via online support form. 05/07/2007 - Vendor response. 25/09/2007 - Vendor informs that fix will be implemented in next release scheduled for December 2007. 04/12/2007 - Vendor informs that release of fixed version is pushed to February 2008. 18/01/2008 - Contacted by QA Manager and offered to test beta release. 22/01/2008 - Vendor contacted to acknowledge that vulnerability is fixed in beta release. 03/03/2008 - Vendor informs that scheduled ship date was missed due to stability issues in fixed version. 13/05/2008 - Status update requested. 16/05/2008 - Vendor informs that ship date is set to end of July 2008. Vendor also states that customer impact is considered minimal as exploitation requires access to the user's system. 19/05/2008 - Vendor contacted, clarifying remote attack vector of the vulnerability, which only requires convincing the user to visit a malicious web site that redirects to the local interface. 17/07/2008 - Status update requested. Vendor informed that disclosure date will not be pushed again as coordination now has taken more than a year from initial vulnerability report. 31/07/2008 - Public disclosure. ====================================================================== 7) Credits Discovered by Carsten Eiram, Secunia Research. ====================================================================== 8) References The Common Vulnerabilities and Exposures (CVE) project has assigned CVE-2007-2952 for the vulnerability. ====================================================================== 9) About Secunia Secunia offers vulnerability management solutions to corporate customers with verified and reliable vulnerability intelligence relevant to their specific system configuration: http://corporate.secunia.com/ Secunia also provides a publicly accessible and comprehensive advisory database as a service to the security community and private individuals, who are interested in or concerned about IT-security. http://secunia.com/ Secunia believes that it is important to support the community and to do active vulnerability research in order to aid improving the security and reliability of software in general: http://corporate.secunia.com/secunia_research/33/ Secunia regularly hires new skilled team members. Check the URL below to see currently vacant positions: http://secunia.com/secunia_vacancies/ Secunia offers a FREE mailing list called Secunia Security Advisories: http://secunia.com/secunia_security_advisories/ ====================================================================== 10) Verification Please verify this advisory by visiting the Secunia website: http://secunia.com/secunia_research/2007-61/ Complete list of vulnerability reports published by Secunia Research: http://secunia.com/secunia_research/ ======================================================================