A stack-based buffer overflow vulnerability exists in Synactis PDF In-The-Box ActiveX control (PDF_IN_1.ocx), specifically the ConnectToSynactis method. When a long string is passed to this method—intended to populate the ldCmdLine argument of a WinExec call—a strcpy operation overwrites a saved TRegistry class pointer on the stack. This allows remote attackers to execute arbitrary code in the context of the user by enticing them to visit a malicious webpage that instantiates the vulnerable ActiveX control. The vulnerability was discovered via its use in third-party software such as Logic Print 2013.
The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.