Zone Labs IMsecure Active Link Filter Bypass http://www.kurczaba.com/html/security/0410141.htm ------------------------------------------------- Overview: A vulnerability has been discovered in the Zone Labs IMsecure Active Link Filter Vendor: Zone Labs (http://www.zonelabs.com) Affected Systems/Configuration: Versions of IMsecure and IMsecure Pro prior to 1.5 Vulnerability/Exploit: The Active Link filter blocks potentially dangerous URLs in IM messages. For example, IMsecure will remove URLs with extensions of .vbs, and .exe. By using hex encoded characters in the file extension of the URL, it is possible to bypass the Active Link filter. Workaround: Upgrade to version 1.5 or higher Proof of Concept: http://www.example.com/somefile.e%78e In the example above, "78" is hex for "x".In plain English, the URL reads: http://www.example.com/somefile.exe Date Discovered: April 1, 2004 Fix Available: October 12, 2004 Severity: Low Credit: Paul Kurczaba Kurczaba Associates