Adobe Systems plans to release emergency patches for its Flash and Reader applications after learning a critical vulnerability is being exploited to install malware on vulnerable machines.
The out-of-cycle patches for Adobe Flash Player 10 and Acrobat and Reader versions 9, 10, and X will arrive during the week March 21, the company said on Monday. The updates will cover all versions of those programs except for Reader X for Windows, which ships with a security sandbox that blocks the exploits Adobe has observed so far.
The announcement comes after members of Adobe's security team received reports of targeted attacks aimed “at a very small number of organizations and limited in scope” that “install persistent malware on the victim's machine,” the company said in an advisory. The exploits wield a booby-trapped Flash file hidden inside a Microsoft Excel file attached to an email.
The attacks exploit an unspecified flaw in Flash Player for the Windows, Mac, Linux, Solaris and Android operating systems. Adobe security members are unaware of other types of attacks, such as those that plant the malicious Flash file in documents using the the PDF, or portable document format, specification.
“However, attackers have leveraged these type [sic] of Flash Player vulnerabilities in the past via .pdf files to attack the embedded authplay.dll component shipping with Adobe Reader and Acrobat v9,” Brad Arkin, Adobe's senior director of product security and privacy, wrote. “Out of a preponderance of caution we took the decision to ship out-of-cycle updates for Adobe Reader and Acrobat v9, and Acrobat X to mitigate the risk of attackers shifting the attack from an .xls container to a .pdf container.”
The unscheduled patch won't cover Reader X for Windows, because that recently released version of the program contains a Sandbox that isolates remotely supplied payloads from the OS's core functions. As a result, the exploits Adobe has seen to date aren't able to successfully execute on machines that run it. Many Reader users, particularly those in corporate settings, still run versions 10 or 9 of Reader, meaning they will remain vulnerable until the emergency patch is installed.
Excluding Reader X for Windows from the out-of-cycle release will allow Adobe engineers to publish it more quickly than it otherwise could. The fix for that version will be released on June 14, during Adobe's next scheduled quarterly update.
Adobe has more here. The critical vulnerability has been assigned CVE-2011-0609. ®