RHSA-2011:1105: Moderate: libpng security update

The libpng packages contain a library of functions for creating andmanipulating PNG (Portable Network Graphics) image format files.A buffer overflow flaw was found in the way libpng processed certain PNGimage 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 runningthe application. (CVE-2011-2690)Note: The application behavior required to exploit CVE-2011-2690 is rarelyused. No application shipped with Red Hat Enterprise Linux behaves thisway, for example.An out-of-bounds memory read flaw was found in the way libpng processedcertain PNG image files. An attacker could create a specially-crafted PNGimage 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 processedcertain PNG images that use the Physical Scale (sCAL) extension. Anattacker 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 upgradelibpng to version 1.2.46 to correct these issues. All running applicationsusing libpng must be restarted for the update to take effect.