Untrusted search path vulnerability in TortoiseSVN 1.6.10, Build 19898 and earlier allows local users, and possibly remote attackers, to execute arbitrary code and conduct DLL hijacking attacks via a Trojan horse dwmapi.dll that is located in the same folder as a file that is processed by Tortoise. NOTE: this is only a vulnerability when a file extension is associated with TortoiseProc or TortoiseMerge, which is not the default.
http://www.securityfocus.com/archive/1/513463/100/0/threaded
http://www.securityfocus.com/archive/1/513442/100/0/threaded
http://tortoisesvn.tigris.org/ds/viewMessage.do?dsForumId=4061&dsMessageId=2653163