Background on APSA11-01 Patch Schedule

We just posted Security Advisory APSA11-01 announcing a critical vulnerability (CVE-2011-0609) in Adobe Flash Player, which also impacts the authplay.dll component shipping with Adobe Reader and Acrobat for Windows and Macintosh.

In the advisory, we referenced the following target ship schedule for the security updates addressing CVE-2011-0609 in Adobe Flash Player, Adobe Reader and Acrobat:

  • The security update for Adobe Flash Player 10.x and earlier versions for Windows, Macintosh, Linux, Solaris and Android is scheduled to be available during the week of March 21, 2011.
  • The security update for Adobe Acrobat X (10.0.1) and earlier 10.x and 9.x versions for Windows and Macintosh, and Adobe Reader 9.4.2 and earlier 9.x versions is also scheduled to be available by the week of March 21, 2011.
  • We currently plan to address CVE-2011-0609 in Adobe Reader X with the next quarterly security update for Adobe Reader, currently scheduled for June 14, 2011.

Let me provide some additional background on the decision not to update Adobe Reader X at this time. We evaluated a number of different options. In the end, we determined that the above patch schedule would allow us to provide the best balance of risk mitigation and admin/update costs for our customers. Here are some points we considered in developing this schedule:

  • Reports that we’ve received thus far indicate the attack is targeted at a very small number of organizations and limited in scope. The current attack leverages a malicious Flash (.swf) file inside a Microsoft Excel (.xls) file. The .xls file is used to set up machine memory to take advantage of a crash triggered by the corrupted .swf file. The final step of the attack is to install persistent malware on the victim’s machine.
  • We have not received reports or malicious samples of attacks leveraging this vulnerability via .pdf files. However, attackers have leveraged these type of Flash Player vulnerabilities in the past via .pdf files to attack the embedded authplay.dll component shipping with Adobe Reader and Acrobat v9. 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.
  • Adobe Reader X Protected Mode (aka “sandboxing”) is designed to prevent the type of exploit we are currently seeing in the .swf/.xls attack from executing. Even if an attacker made the transition to a .pdf container for the exploit, the sandbox would prevent the final step of malicious software installation on the victim’s machine.
  • We considered providing an out-of-cycle update for Adobe Reader X as well, which would have delayed the current patch release schedule by about another week. However, given the mitigation provided by the Adobe Reader X sandbox and the absence of attacks via PDF, we determined that an out-of-cycle update would incur unnecessary churn and patch management overhead on our users not justified by the associated risk, in particular for customers with large managed environments.

We are working closely with our Microsoft Active Protections Partners (MAPP), customers and other partners in the security community to monitor the situation. Should we see different types of exploits targeting CVE-2011-0609 in Adobe Reader X, we will update our current plan accordingly.

Brad Arkin
Senior Director, Product Security and Privacy