Phase:Various Intrusion Detection Systems (IDS) including (1) Cisco Secure Intrusion Detection System, (2) Cisco Catalyst 6000 Intrusion Detection System Module, (3) Dragon Sensor 4.x, (4) Snort before 1.8.1, (5) ISS RealSecure Network Sensor 5.x and 6.x before XPU 3.2, and (6) ISS RealSecure Server Sensor 5.5 and 6.0 for Windows, allow remote attackers to evade detection of HTTP attacks via non-standard "%u" Unicode encoding of ASCII characters in the requested URL.
ReferencesBUGTRAQ:Wednesday, September 05, 2001 %u encoding IDS bypass vulnerability | URL:http://marc.theaimsgroup.com/?l=bugtraq&m=99972950200602&w=2 | ISS:Wednesday, September 05, 2001 Multiple Vendor IDS Unicode Bypass Vulnerability | URL:http://xforce.iss.net/alerts/advise95.php | CISC
Votes:Modified (Tuesday, May 10, 2005)
Comments: ACCEPT(4) Baker, Cole, Armstrong, Balinsky | MODIFY(1) Frech | NOOP(2) Wall, Foat
F7: Frech> XF:iis-unicode-encoding-detected(6994) | XF:iis-unicode-wide-encoding(6995)