[ GLSA 200701-06 ] w3m: Format string vulnerability

[GLSA]

Gentoo Linux Security Advisory

Title: w3m: Format string vulnerability (GLSA 200701-06)
Severity: normal
Exploitable: remote
Date: January 12, 2007
Bug(s): #159145
ID: 200701-06

Synopsis


w3m does not correctly handle format string specifiers in SSL certificates.


Background


w3m is a multi-platform text-based web browser.


Affected Packages

Package: www-client/w3m
Vulnerable: < 0.5.1-r4
Unaffected: >= 0.5.1-r4
Architectures: All supported architectures


Description


w3m in -dump or -backend mode does not correctly handle printf() format
string specifiers in the Common Name (CN) field of an X.509 SSL
certificate.


Impact


An attacker could entice a user to visit a malicious website that would
load a specially crafted X.509 SSL certificate containing "%n" or other
format string specifiers, possibly resulting in the execution of
arbitrary code with the rights of the user running w3m.


Workaround


There is no known workaround at this time.


Resolution


All w3m users should upgrade to the latest version: