Adobe Plugs 0day Flash Hole Found by Kaspersky

Summary:

• This vulnerability affects: Adobe Flash Player  12.0.0.43 and earlier, running on all platforms
• How an attacker exploits it: Typically, by enticing users to visit a website containing malicious Flash content
• Impact: An attacker can execute code on the user’s computer, potentially gaining control of it
• What to do: Download and install the latest version of Adobe Flash Player (version 12.0.0.44 for most computers)

Exposure:

Adobe Flash Player displays interactive, animated web content called Flash. Although Flash is optional, 99% of PC users download and install it to view multimedia web content. It runs on many operating systems, including mobile ones like Android. It also comes prepackaged with some web browsers like Chome and the latest version of Internet Explorer (IE).

In an out-of-cycle security bulletin released today, Adobe posted an update that fixes a critical, zero day vulnerability in Adobe Flash Player 12.0.0.43 and earlier, running on all platforms. We urge Flash users to install this update as soon as possible, since advanced attackers are exploiting it in the wild.

Adobe’s bulletin describes an integer overflow vulnerability (CVE-2014-0497) in Flash player, which attackers have been exploiting in the wild. In typical fashion, Adobe’s bulletin doesn’t describe the flaw in much technical detail, but they do describe its impact. If an attacker can entice one of your users to visit a malicious website, or into handling specially crafted Flash content (which could be embedded in a document), he could exploit this flaw to execute code on that user’s computer, with that user’s privileges. If your users have administrator privileges, the attacker could gain full control of their computers.

This particular flaw was brought to Adobe’s attention by one of Kaspersky’s (one of WatchGuard’s antivirus partners) researchers. Yesterday, members of Kaspersky’s research team announced that they plan on disclosing details about a new advanced persistent threat (APT) campaign later next week, which they call “The Mask.” According to some reports, this Flash zero day exploit might be associated with that cyber espionage campaign.

In any case, Adobe has assigned this a “Priority 1” severity rating for Windows and Macintosh computers, which means you should fix it within 72 hours. If you use Flash, I recommend you apply the update as soon as possible.

Solution Path

Adobe has released new versions of Flash Player (12.0.0.44 for Windows and Mac) to fix these issues. If you allow Adobe Flash in your network, you should download and install the new versions immediately. If you’ve enabled Flash Player’s recent “silent update” option, you will receive this update automatically.

• Download Flash Player for your computer:

For All WatchGuard Users:

If you choose, you can configure the HTTP proxy on your XTM appliance to block Flash content. Keep in mind, doing so blocks all Flash content, whether legitimate or malicious.

Our proxies offer many ways for you to block files and content, including by file extension, MIME type, or by using very specific hexidecimal patterns found in the body of a message – a technique sometimes referred to as Magic Byte detection. Below I list the various ways you can identify various Flash files:

File Extension:

• .flv –  Adobe Flash file (file typically used on websites)
• .fla – Flash movie file
• .f4v – Flash video file
• .f4p – Protected Flash video file
• .f4a – Flash audio file
• .f4b – Flash audiobook file

MIME types:

• video/x-flv
• video/mp4 (used for more than just Flash)
• audio/mp4 (used for more than just Flash)

FILExt.com reported Magic Byte Pattern:

• Hex FLV: 46 4C 56 01
• ASCII FLV: FLV
• Hex FLA:  D0 CF 11 E0 A1 B1 1A E1 00

(Keep in mind, not all the Hex and ASCII patterns shared here are appropriate for content blocking. If the pattern is too short, or not unique enough, blocking with them could result in many false positives) 

If you decide you want to block Flash files, the links below contain instructions that will help you configure your Firebox proxy’s content blocking features using the file and MIME information listed above.

• XTM Appliance with WSM 11.x
  • How do I block files with the FTP proxy?
  • How do I block files with the HTTP proxy?
  • How do I block files with the POP3 proxy?
  • How do I block files with the SMTP Proxy?

• Firebox X Edge running 10.x
  • How do I block files with the FTP proxy?
  • How do I block files with the HTTP proxy?
  • How do I block files with the POP3 proxy?
  • How do I block files with the SMTP proxy

• Firebox X Core and X Peak running Fireware 10.x
  • How do I block files with the FTP proxy?
  • How do I block files with the HTTP proxy?
  • How do I block files with the POP3 proxy?
  • How do I block files with the SMTP proxy?

Status:

Adobe has released updates to fix these Flash vulnerabilities.

References:

• February 2014 Adobe Flash Security Bulletin

This alert was researched and written by Corey Nachreiner, CISSP (@SecAdept)