The Chilkat XML ChilkatUtil.CkData.1 ActiveX control (ChilkatUtil.dll) 3.0.3.0 and earlier allows remote attackers to create, overwrite, and modify arbitrary files for execution via a call to the (1) SaveToFile, (2) SaveToTempFile, or (3) AppendBinary method.  NOTE: this issue might only be exploitable in limited environments or non-default browser settings.  NOTE: this can be leveraged for remote code execution by accessing files using hcp:// URLs.