A security flaw in the popular document-sharing software, Adobe Reader, could be exploited to seize control of a computer system, according to the software's maker. Adobe Systems Inc. issued a warning on its Web site Tuesday saying that the flaw affects only the Adobe Reader versions 5.0.9, 5.0.10, which were written for the Unix computer operating system. A hacker could exploit the security breach by e-mailing maliciously written PDF files. Unsuspecting computer users who open the PDF files would expose their hard drives to attack, according to San Jose-based Adobe.
Adobe posted a fix, http://www.adobe.com/support/techdocs/329083.html, for the vulnerability on its site, and a spokesman said Wednesday he was unaware of any security breaches resulting from the software flaw, which was discovered by the security defense firm IDefense, headquartered in Reston, Va. Known for its imaging software Photoshop and Acrobat, Adobe has distributed more than 500 million free copies of Adobe Reader since it was introduced in 1993. Only a small percentage were written for Unix.