The TIFFExtractData macro in LibTIFF before 3.9.4 does not properly handle unknown tag types in TIFF directory entries, which allows remote attackers to cause a denial of service (out-of-bounds read and application crash) via a crafted TIFF file.
http://www.vupen.com/english/advisories/2010/1761
http://www.redhat.com/support/errata/RHSA-2010-0519.html
http://www.openwall.com/lists/oss-security/2010/06/30/22
http://security.gentoo.org/glsa/glsa-201209-02.xml
http://secunia.com/advisories/50726
http://secunia.com/advisories/40527
http://marc.info/?l=oss-security&m=127797353202873&w=2
http://marc.info/?l=oss-security&m=127781315415896&w=2
http://marc.info/?l=oss-security&m=127738540902757&w=2