According to Adobe, the issue is an U3D memory corruption vulnerability that can be exploited to cause a crash and permit an attacker to hijack a system. So far, there are reports the vulnerability is being exploited in limited, targeted attacks against Adobe Reader 9.x on Windows. However, the bug also affects Adobe Reader and Acrobat 9.4.6 and earlier 9.x versions for UNIX and Macintosh computers, as well as Adobe Reader X (10.1.1) and Acrobat X (10.1.1) and earlier 10.x versions on Windows and Mac.
Patches for Windows and Mac users of Adobe Reader X and Acrobat X will come on the next quarterly update, scheduled for Jan. 10, 2012."
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