source: https://www.securityfocus.com/bid/666/info
There is a buffer overflow in the 1.3.188 version of the Adobe Acrobat ActiveX control (pdf.ocx) that ships with Acrobat Viewer 4.0. This ActiveX control is marked 'Safe for Scripting' within Internet Explorer 4.X. Arbitrary commands may be executed if the ActiveX control is run in a malicious manner
This control from Adobe Acrobat, can be exploited through
the setview method, and because ESP points to the address
after the RET address, we can place arbitrary code at this
point and JMP to it by RET'ing to a JMP ESP, in this case,
one found in Shell32. The code simply executes CALC.EXE
then calls ExitProcess to terminate the host without it
crashing. I have attempted to notify Adobe of the issue,
however they don't appear to have any form of direct
secure@ address.