Critical vulnerabilities have been identified in Adobe Reader 9.1.3 and Acrobat 9.1.3, Adobe Reader 8.1.6 and Acrobat 8.1.6 for Windows, Macintosh and UNIX, and Adobe Reader 7.1.3 and Acrobat 7.1.3 for Windows and Macintosh. 

These vulnerabilities could cause the application to crash and could potentially allow an attacker to take control of the affected system. 

This update represents the second quarterly security update for Adobe Reader and Acrobat. 

Adobe recommends users of Adobe Reader 9.1.3 and Acrobat 9.1.3 and earlier versions update to Adobe Reader 9.2 and Acrobat 9.2. Users of Acrobat 8.1.6 and earlier versions update to Acrobat 8.1.7, and users of Acrobat 7.1.3 and earlier versions update to Acrobat 7.1.4. 

For Adobe Reader users who cannot update to Adobe Reader 9.2, Adobe has provided the Adobe Reader 8.1.7 and Adobe Reader 7.1.4 updates. 

Updates apply to all platforms: Windows, Macintosh and UNIX

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