libpng: Denial of service

Background

libpng is a free ANSI C library used to process and manipulate PNG images.

Description

Mats Palmgren fixed an error in file pngrutil.c in which the trans[] array might be not allocated because of images with a bad tRNS chunk CRC value.

Impact

A remote attacker could craft an image that when processed or viewed by an application using libpng causes the application to terminate abnormally.

Workaround

There is no known workaround at this time.

Resolution

Please note that due to separate bugs in libpng 1.2.17, Gentoo does not provide libpng-1.2.17 but libpng-1.2.18. All libpng users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=media-libs/libpng-1.2.18"