CVE 2005-0525
The php_next_marker function in image.c for PHP 4.2.2, 4.3.9, 4.3.10 and 5.0.3, as reachable by the getimagesize PHP function, allows remote attackers to cause a denial of service (infinite loop) via a JPEG image with an invalid marker value, which causes a negative length value to be passed to php_stream_seek.
See the 
CVE page on Mitre.org
for more details.
