Weex: Format string vulnerability

Background

Weex is a non-interactive FTP client typically used to update web pages.

Description

Ulf Harnhammar discovered a format string bug in Weex that can be triggered when it is first run (or when its cache files are rebuilt, using the -r option).

Impact

An attacker could setup a malicious FTP server which, when accessed using Weex, could trigger the format string bug and end up executing arbitrary code with the rights of the user running Weex.

Workaround

There is no known workaround at this time.

Resolution

All Weex users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=net-ftp/weex-2.6.1.5-r1"