The SmartHTML Interpreter (shtml.dll) is part of the FrontPage Server Extensions (FPSE), and provides support for web forms and other FrontPage-based dynamic content. The interpreter contains a flaw that could be exposed when processing a request for a particular type of web file, if the request had certain specific character-istics. This flaw affects the two versions of FrontPage Server Extensions differently. On FrontPage Server Extensions 2000, such a request would cause the interpreter to consume most or all CPU availability until the web service was restarted. An attacker could use this vulnerability to conduct a denial of service attack against an affected web server. On FrontPage Server Extensions 2002, the same type of request could cause a buffer overrun, potentially allowing an attacker to run code of his choice.
Title: Buffer Overrun in SmartHTML Interpreter Could Allow Code Execution (Q324096)
Released: 25 September 2002
Software: FrontPage Server Extensions 2000 and 2002
Impact: Denial of service or privilege elevation
Max Risk: Critical
Bulletin: MS02-053
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