Sophos Anti-Virus for Windows and for Unix/Linux before 2.48.0 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a crafted UPX packed file, resulting from an "integer cast around". NOTE: as of 20070828, the vendor says this is a DoS and the researcher says this allows code execution, but the researcher is reliable.
http://www.vupen.com/english/advisories/2007/2972
http://www.sophos.com/support/knowledgebase/article/28407.html
http://www.securityfocus.com/bid/25428
http://www.securityfocus.com/archive/1/477882/100/0/threaded
http://www.securityfocus.com/archive/1/477864/100/0/threaded
http://www.securityfocus.com/archive/1/477720/100/0/threaded
http://www.nruns.com/security_advisory_sophos_upx_infinite_loop_dos.php
http://securitytracker.com/id?1018608