DSUtility.dll in Pelco Digital Sentry Server before 7.19.67 has an arbitrary file write vulnerability. The AppendToTextFile method doesn't check if it's being called from the application or from a malicious user. The vulnerability is triggered when a remote attacker crafts an HTML page (e.g., with "OBJECT classid=" and "<SCRIPT language='vbscript'>") to overwrite arbitrary files.
