RHSA-2015:2595 — Security Advisory

Updated libpng12 packages that fix three security issues are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having Moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

The libpng12 packages contain a library of functions for creating and manipulating PNG (Portable Network Graphics) image format files.

It was discovered that the png_get_PLTE() and png_set_PLTE() functions of libpng did not correctly calculate the maximum palette sizes for bit depths of less than 8. In case an application tried to use these functions in combination with properly calculated palette sizes, this could lead to a buffer overflow or out-of-bounds reads. An attacker could exploit this to cause a crash or potentially execute arbitrary code by tricking an unsuspecting user into processing a specially crafted PNG image. However, the exact impact is dependent on the application using the library. (CVE-2015-8126, CVE-2015-8472)

An array-indexing error was discovered in the png_convert_to_rfc1123() function of libpng. An attacker could possibly use this flaw to cause an out-of-bounds read by tricking an unsuspecting user into processing a specially crafted PNG image. (CVE-2015-7981)

All libpng12 users are advised to upgrade to these updated packages, which contain backported patches to correct these issues.