According to a security advisory from Adobe, there is a critical vulnerability in Flash Player 10.0.45.2 (and earlier versions) and in the authplay.dll component that ships with Adobe Reader and Acrobat 9.0; Windows, Mac OS X, Unix and Linux versions are all vulnerable. Attackers can exploit the hole to crash the software or gain control of the system and there are already reports of exploitation in the wild for all three products.
The Flash Player 10.1 release candidate is apparently not vulnerable and Adobe offer the option of installing this as a mitigation step. For Reader and Acrobat 9.x, Adobe recommend deleting, renaming or removing access to the authplay.dll file to mitigate the threat. On Windows, this file is typically located at C:\Program Files\Adobe\Reader 9.0\Reader\authplay.dll for Adobe Reader or C:\Program Files\Adobe\Acrobat 9.0\Acrobat\authplay.dll for Acrobat. Adobe say that Reader and Acrobat 8.x are not vulnerable.

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