GIF handling code used in netpbm's giftopnm converter is based on the same code as used by gd and SDL_image and is affected by the overflow known as CVE-2006-4484 and CVE-2007-6697. readImageData function in giftopnm.c does not properly check the value of lzwMinCodeSize value read from GIF image before passing it to lzwInit, which uses it as upper bound during the initialization of fixed sized table array, leading to a buffer overflow. This issue was fixed in upstream version 10.27. Code checking the value is in the initial giftopnm.c revision in projects public SVN repository: http://netpbm.svn.sourceforge.net/viewvc/netpbm/trunk/converter/other/giftopnm.c?revision=1&view=markup#l_1052 This issue does not affect netpbm packages as shipped in Red Hat Enterprise Linux 5 and current versions of Fedora, as those packages are based on fixed upstream version. Related issues: CVE-2006-4484 (gd), CVE-2007-6697 (SDL_image), CVE-2008-0553 (tk)
This issue does not affect versions of netpbm as shipped with Red Hat Enterprise Linux 5 and Fedora 7 and 8, as those are based on upstream version which already contains the patch.
This issue was addressed in: Red Hat Enterprise Linux: http://rhn.redhat.com/errata/RHSA-2008-0131.html