Adobe has been forced to issue yet another emergency patch to fix critical flaws in Reader and Acrobat.
The vulnerabilities have been identified in Adobe Reader 9.4 and earlier versions for Windows, Macintosh and Unix, and Adobe Acrobat 9.4 and earlier 9.x versions for Windows and Macintosh.
Adobe said in a security bulletin that the flaws could cause the applications to crash or, more seriously, allow hackers to take control of affected systems.
The out-of-band updates also resolve a memory corruption vulnerability that could lead to code execution.
The Adobe Reader flaw has been known about since the end of October, and Adobe acknowledged in a security bulletin that it has already been exploited in the wild.
Adobe's next quarterly security update is on 8 February, but there is no guarantee that more emergency patches will not be issued between now and then, given that the firm's software is one of the most highly targeted by hackers.
The company has also warned users to be careful of phishing scams using the offer of the latest version of Acrobat or Reader as a lure to harvest personal information.
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