Adobe today confirmed that hackers are exploiting a critical unpatched bug in Flash Player, and promised to patch the vulnerability in two weeks.
The company issued a security advisory that also named Adobe Reader and Acrobat as vulnerable.
The report followed a recent announcement by Adobe that it has quickly developed a fix a potentially serious flaw discovered in its Shockwave application. That fix will be available this Thursday.
“There are reports that this vulnerability is being actively exploited in the wild against Adobe Reader and Acrobat,” said Adobe in its warning. The company said it’s seen no sign that hackers are also targeting Flash Player itself.
Those reports came from Mila Parkour, an independent security researcher who notified Adobe early today after spotting and then analyzing a malicious PDF file. According to Parkour, the rigged PDF document exploits the Flash bug in Reader, then drops a Trojan horse and other malware on the victimized machine.
Adobe said that all versions of Flash on Windows, Mac, Linux and Android harbored the bug, and that the “Authplay” component of Reader and Acrobat 9.x and earlier also contained the flaw. Authplay is the interpreter that renders Flash content embedded within PDF files.
The Adobe security advisory explains, “A critical vulnerability exists in Adobe Shockwave Player 126.96.36.1992 and earlier versions on the Windows and Macintosh operating systems. This vulnerability (CVE-2010-3653) could cause a crash and potentially allow an attacker to take control of the affected system.”
The Shockwave Player is installed on more than 450 million Windows and Mac PCs. Shockwave may seem redundant when compared with Adobe Flash–both being Adobe applications dedicated to online interactive content.
The utility of the two programs are, in fact, quite similar. Shockwave is for content created with Adobe Director, and is geared toward multi-user games, interactive 3D simulations, online entertainment, and tutorials. Flash Player, on the other hand, is for content created with Adobe Flash Professional, and tends to be used more for Web site front-ends, online advertising, animations, and video content.
Adobe is stingy with the details of exactly what the flaw is, or how it might be exploited, but the security advisory does disclose the potential consequences of a successful exploit. A system crash is a nuisance, and is obviously undesirable, but any flaw that can be exploited to allow the attacker to take control of the vulnerable system is worth investigating and patching.
Adobe software is generally cross-platform and ubiquitous, making it an increasingly attractive target for malware developers. Adobe has moved quickly to develop a patch for this Shockwave vulnerability, and affected systems should be patched as soon as possible before attackers have time to figure out how to exploit it.
Adobe stresses that while this is a potentially serious issue, and the details have been publicly disclosed, there are no reports of the vulnerability being exploited in the wild.
New Flash vulnerability
Last month, Parkour uncovered a bug in Reader’s font-rendering technology that was exploited by attack campaigns using bogus messages from renowned golf coach David Leadbetter as click bait.
Today’s vulnerability, however, is more reminiscent of one reported in June that also involved Authplay. Adobe issued an emergency patch for Flash Player within a week, and followed with a fix for Reader and Acrobat two weeks later.
Adobe will patch this newest bug in a similar fashion. Today it promised to issue a fix for Flash by Nov. 9, and updates for Reader and Acrobat the following week.
Danish vulnerability tracker Secunia ranked the Flash flaw as “extremely critical,” its highest threat ranking, and said criminals could use it to compromise systems and execute malicious code.
Security experts have regularly criticized Adobe Flash’s security, with some questioning the company’s decision to integrate the media player’s capabilities within the almost-as-popular Reader. Adobe has countered those arguments with its own, saying that many users rely on the functionality.
Until a patch is available, users can protect themselves from active attacks by deleting the “authplay.dll” file that ships with Reader and Acrobat. It gave the same advice in June when the earlier Flash vulnerability was reported.
Dumping authplay.dll, however, will crash Reader and Acrobat or produce an error message when the software opens a PDF file containing Flash content.
Today’s Flash flaw disclosure was the second Adobe’s acknowledged since the technology was ported to Google’s Android operating system two months ago.
Although Adobe tries to hew to a quarterly patch schedule for Reader and Acrobat, it’s repeatedly been forced to scuttle those plans to issue rush fixes for critical bugs. The next regularly-scheduled Reader update was not supposed to land until Feb. 8, 2011.
At times, Adobe has abandoned scheduled Reader updates after shipping an “out-of-band” patch, but that’s unlikely here as the company is in the early days of its next patch cycle.