Software Engineering Institute

A critical vulnerability exists in the font parsing code in Adobe Reader and Acrobat. The vulnerability results in memory corruption, which could allow for the execution of arbitrary code.

An attacker may use a specifically crafted PDF document to cause a crash or execute arbitrary code.

Apply an update

Adobe recommends all users upgrade to Adobe Reader and Acrobat 10.1, 9.4.5, or 8.3. APSB11-16 contains more details. Please also consider the following workarounds:

Use the Microsoft Enhanced Mitigation Experience Toolkit

The Microsoft Enhanced Mitigation Experience Toolkit (EMET) can be used to help prevent exploitation of this and other vulnerabilities.

Enable DEP in Microsoft Windows

Consider enabling Data Execution Prevention (DEP) in supported versions of Windows. DEP should not be treated as a complete workaround, but it can mitigate the execution of attacker-supplied code in some cases. Microsoft has published detailed technical information about DEP in Security Research & Defense blog posts "Understanding DEP as a mitigation technology" part 1 and part 2. DEP should be used in conjunction with the application of patches or other mitigations described in this document.

Note that when relying on DEP for exploit mitigation, it is important to use a system that supports Address Space Layout Randomization (ASLR) as well. ASLR is not supported by Windows XP or Windows Server 2003 or earlier. ASLR was introduced with Microsoft Windows Vista and Windows Server 2008. Please see the Microsoft SRD blog entry: On the effectiveness of DEP and ASLR for more details.

Disable JavaScript in Adobe Reader and Acrobat

Disabling JavaScript helps to reduce attack surface and mitigates some exploitation techniques. If this workaround is applied to updated versions of Adobe Reader and Acrobat, it may protect against future vulnerabilities.

To disable JavaScript in Adobe Reader:

1. Open Adobe Acrobat Reader.
2. Open the Edit menu.
3. Choose the Preferences... option.
4. Choose the JavaScript section.
5. Uncheck the Enable Acrobat JavaScript checkbox.

1. Open Adobe Acrobat Reader.
2. Open the Edit menu.
3. Choose the Preferences... option.
4. Choose the Internet section.
5. Uncheck the Display PDF in browser checkbox.