Use-after-free vulnerability in the GIFReadNextExtension function in lib/pngxtern/gif/gifread.c in OptiPNG 0.6.2 and earlier allows context-dependent attackers to cause a denial of service (application crash) via a crafted GIF image that causes the realloc function to return a new pointer, which triggers memory corruption when the old pointer is accessed.
https://exchange.xforce.ibmcloud.com/vulnerabilities/48879
http://www.openwall.com/lists/oss-security/2009/02/25/4
http://www.openwall.com/lists/oss-security/2009/02/24/2
http://www.gentoo.org/security/en/glsa/glsa-200903-12.xml
http://sourceforge.net/tracker/index.php?func=detail&aid=2582013&group_id=151404&atid=780913
http://optipng.sourceforge.net
http://lists.opensuse.org/opensuse-security-announce/2009-07/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2009-03/msg00001.html