OptiPNG: User-assisted execution of arbitrary code

Background

OptiPNG is a PNG optimizer that recompresses image files to a smaller size, without losing any information.

Description

A use-after-free vulnerability exists in the palette reduction functionality of OptiPNG.

Impact

A remote attacker could entice a user to open a specially crafted image file, possibly resulting in execution of arbitrary code with the privileges of the process or a Denial of Service condition.

Workaround

There is no known workaround at this time.

Resolution

All OptiPNG users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=media-gfx/optipng-0.7.3"