The gdk_pixbuf__gif_image_load function in gdk-pixbuf/io-gif.c in gdk-pixbuf before 2.23.5 does not properly handle certain return values, which allows remote attackers to cause a denial of service (memory consumption) via a crafted GIF image file.
http://security.gentoo.org/glsa/glsa-201206-20.xml
http://secunia.com/advisories/49715
http://secunia.com/advisories/45656
http://ftp.gnome.org/pub/GNOME/sources/gdk-pixbuf/2.23/gdk-pixbuf-2.23.5.news