There is a buffer overflow in Internet Explorer when IE receives information from a gopher service.
Gopher is a protocol that presents documents and services in a hierarchal representation, and is similar in some ways to HTTP. Internet Explorer reportedly contains a buffer overflow in the code that processes responses from gopher servers. Although gopher servers are no longer widely supported, Internet Explorer supports gopher. If an intruder can entice or coerce a victim into clicking on a link to a gopher server, and the intruder can control the response from the gopher server (perhaps by constructing his own malicious gopher server), the intruder may be able to use the buffer overflow to execute arbitrary code with the privileges of the victim.
This issue was discovered by Jouko Pynnonen of Online Solutions Ltd . Additional information can be found at http://www.solutions.fi/index.cgi/news_2002_06_04?lang=eng and http://microsoft.com/technet/treeview/default.asp?url=/technet/security/bulletin/MS02-027.asp.
Intruders may be able to execute arbitrary code with the privileges of the victim.
Remove the gopher URL handler from IE, and block requests to gopher servers (TCP/70) and your network perimeter.
Our thanks to Oy Online SOlutions LTD, upon whose advisory this document is based, and who discovered the vulnerability.
This document was written by Shawn V. Hernan & Ian A. Finlay.
|Date First Published:||2002-06-12|
|Date Last Updated:||2002-06-12 19:00 UTC|