Software Engineering Institute

Adobe Flash is a widely deployed multimedia platform typically used to provide content in web sites. Adobe Flash Player, Reader, Acrobat, and other Adobe products include Flash support.

Adobe Flash Player contains a code execution vulnerability. An attacker may be able to trigger this vulnerability by convincing a user to open a specially crafted Flash (SWF) file. The SWF file could be hosted or embedded in a web page or contained in a Portable Document Format (PDF) file. If an attacker can take control of a website or web server, trusted sites may exploit this vulnerability.

This vulnerability affects Adobe Flash versions 9.0.159.0 and 10.0.22.87 and earlier 9.x and 10.x versions. Adobe Reader 9, Acrobat 9, and other Adobe products (including Photoshop CS3, PhotoShop Lightroom, Freehand MX, Fireworks) provide Flash support independent of Flash Player. As of 2009-07-22, Adobe Reader 9.1.2 includes Flash 9.0.155.0, which is likely vulnerable to issues addressed by Flash 9.0.159.0 (APSB09-01).

This vulnerability is being actively exploited.

By convincing a user to view a specially crafted HTML document (e.g., a web page or an HTML email message or attachment), PDF file, Microsoft Office document, or any other document that supports embedded SWF content, an attacker may be able to execute arbitrary code.

Apply an update
This issue is addressed in Flash Player 10.0.32.18. Please see Adobe Security Bulletin APSB09-10 for more details. Note that Microsoft Windows users should update both the ActiveX and Plug-in versions of Flash Player for increased protection.

Disable Flash in your web browser

Disable Flash or selectively enable Flash content as described in Securing Your Web Browser.

Disable Flash and 3D & Multimedia support in Adobe Reader 9

Flash and 3D & Multmedia support are implemented as plugin libraries in Adobe Reader. Disabling Flash in Adobe Reader will only mitigate attacks using a SWF embedded in a PDF file. Disabling 3D & Multimedia support does not directly address the vulnerability, but does provide additional mitigation and results in a more user-friendly error message instead of a crash.

To disable Flash and 3D & Multimedia support in Adobe Reader 9 on Microsoft Windows, delete or rename these files:

"%ProgramFiles%\Adobe\Reader 9.0\Reader\authplay.dll"
"%ProgramFiles%\Adobe\Reader 9.0\Reader\rt3d.dll"
For Apple Mac OS X, delete or rename these files:

"/Applications/Adobe Reader 9/Adobe Reader.app/Contents/Frameworks/AuthPlayLib.bundle"
"/Applications/Adobe Reader 9/Adobe Reader.app/Contents/Frameworks/Adobe3D.framework"
For GNU/Linux delete or rename these files (locations may vary among distributions):

"/opt/Adobe/Reader9/Reader/intellinux/lib/libauthplay.so"
"/opt/Adobe/Reader9/Reader/intellinux/lib/librt3d.so"
File locations may be different for Adobe Acrobat or other Adobe products that include Flash and 3D & Multimedia support. Disabling these plugins will reduce functionality, and will not protect against SWF files hosted on web sites. Depending on the update schedule for products other than Flash Player, consider leaving Flash and 3D & Multimedia support disabled unless they are absolutely required.

Remove Flash

Adobe has provided a TechNote with utilities for uninstalling the Flash Player plug-in and ActiveX control on Windows and Mac OS X systems. Removing these components can mitigate the web browser attack vector for this vulnerability. Note that this will not remove the instances of Flash Player that is installed with Adobe Reader 9 or other Adobe products.

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 DEP 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. Use of DEP should be considered in conjunction with the application of patches or other mitigations described in this document.