w3m does not correctly handle format string specifiers in SSL certificates.
|Package||www-client/w3m on all architectures|
|Affected versions||< 0.5.1-r4|
|Unaffected versions||>= 0.5.1-r4|
w3m is a multi-platform text-based web browser.
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.
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.
There is no known workaround at this time.
All w3m users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=www-client/w3m-0.5.1-r4"
January 12, 2007
January 12, 2007: 01