Flaw in Adobe Reader 8.1

The hacker who discovered a recently patched QuickTime flaw affecting the Firefox browser says he has found an equally serious flaw in Adobe Systems Inc.'s PDF file format.

"Adobe Acrobat/Reader PDF documents can be used to compromise your Windows box. Completely!!! Invisibly and unwillingly!!!," wrote Petko Petkov, in a breathless Thursday blog posting. "All it takes is to open a PDF document or stumble across a page which embeds one."

Petkov said he had confirmed the issue on Adobe Reader 8.1 on Windows XP and that other versions may be affected.

The security researcher said he would not release code that shows how this attack works until Adobe provided a patch for the problem, but he has already sent other software developers scrambling for bug fixes over the past week.

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