Hi all, Just want to let you know that Sophos has updated their advisory: http://www.sophos.com/support/knowledgebase/article/28407.html To make things a bit more clear, it's a one byte overwrite in an arbitrary location caused by an integer handling issue while parsing the UPX file format. The advisory at http://www.nruns.com/security_advisory.php will be updated soon. Cheers, Sergio