RHSA-2011:1105 - Security Advisory

Topic

Updated libpng packages that fix multiple security issues are now available
for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team 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.

Description

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

A buffer overflow flaw was found in the way libpng processed certain PNG
image files. An attacker could create a specially-crafted PNG image that,
when opened, could cause an application using libpng to crash or,
potentially, execute arbitrary code with the privileges of the user running
the application. (CVE-2011-2690)

Note: The application behavior required to exploit CVE-2011-2690 is rarely
used. No application shipped with Red Hat Enterprise Linux behaves this
way, for example.

An out-of-bounds memory read flaw was found in the way libpng processed
certain PNG image files. An attacker could create a specially-crafted PNG
image that, when opened, could cause an application using libpng to crash.
(CVE-2011-2501)

An uninitialized memory read issue was found in the way libpng processed
certain PNG images that use the Physical Scale (sCAL) extension. An
attacker could create a specially-crafted PNG image that, when opened,
could cause an application using libpng to crash. (CVE-2011-2692)

Users of libpng should upgrade to these updated packages, which upgrade
libpng to version 1.2.46 to correct these issues. All running applications
using libpng must be restarted for the update to take effect.

Solution

Before applying this update, make sure all previously-released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/kb/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.1 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.1 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 i386
• Red Hat Virtual Storage Appliance (from RHUI) 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension (for IBM z Systems) 6 s390x

Fixes

• BZ - 717084 - CVE-2011-2501 libpng: regression of CVE-2004-0421 in 1.2.23+
• BZ - 720607 - CVE-2011-2690 libpng: buffer overwrite in png_rgb_to_gray
• BZ - 720612 - CVE-2011-2692 libpng: Invalid read when handling empty sCAL chunks

CVEs

• CVE-2011-2692
• CVE-2011-2690
• CVE-2011-2501

References

• https://access.redhat.com/security/updates/classification/#moderate