Moderate: libtiff security update

Updated libtiff packages that fix several security issues are now available
for Red Hat Enterprise Linux 3, 4, and 5.

This update has been rated as having moderate security impact by the Red
Hat Security Response Team.

The libtiff packages contain a library of functions for manipulating Tagged
Image File Format (TIFF) files.

Several integer overflow flaws, leading to heap-based buffer overflows,
were found in various libtiff color space conversion tools. An attacker
could create a specially-crafted TIFF file, which once opened by an
unsuspecting user, would cause the conversion tool to crash or,
potentially, execute arbitrary code with the privileges of the user running
the tool. (CVE-2009-2347)

A buffer underwrite flaw was found in libtiff's Lempel-Ziv-Welch (LZW)
compression algorithm decoder. An attacker could create a specially-crafted
LZW-encoded TIFF file, which once opened by an unsuspecting user, would
cause an application linked with libtiff to access an out-of-bounds memory
location, leading to a denial of service (application crash).
(CVE-2009-2285)

The CVE-2009-2347 flaws were discovered by Tielei Wang from ICST-ERCIS,
Peking University.

All libtiff users should upgrade to these updated packages, which contain
backported patches to correct these issues. After installing this update,
all applications linked with the libtiff library (such as Konqueror) must
be restarted for the update to take effect.

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

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

507465 - CVE-2009-2285 libtiff: LZWDecodeCompat underflow
510041 - CVE-2009-2347 libtiff: integer overflows in various inter-color spaces conversion tools (crash, ACE)

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-2285
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-2347
http://www.redhat.com/security/updates/classification/#moderate