Mozilla Foundation Security Advisory 2011-31

Security issues addressed in Thunderbird 6

August 16, 2011
Fixed in
  • Thunderbird 6

Many of the issues listed below are not exploitable through mail since JavaScript is disabled by default in Thunderbird. These particular issues may be triggered while viewing RSS feeds and displaying full remote content rather than the feed summary. Addons that expose browser functionality may also enable such issues to be exploited.

Miscellaneous memory safety hazards (rv:4.0)

Impact: Critical
Description: Mozilla identified and fixed several memory safety bugs in the browser engine used in Thunderbird 5 and other Mozilla-based products. Some of these bugs showed evidence of memory corruption under certain circumstances, and we presume that with enough effort at least some of these could be exploited to run arbitrary code.


Aral Yaman reported a WebGL crash which affected Thunderbird 5.

Vivekanand Bolajwar reported a JavaScript crash which affected Thunderbird 5.

Bert Hubert and Theo Snelleman of Fox-IT reported a crash in the Ogg reader which affected Thunderbird 5.

Mozilla developers and community members Robert Kaiser, Jesse Ruderman, moz_bug_r_a4, Mardeg, Gary Kwong, Christoph Diehl, Martijn Wargers, Travis Emmitt, Bob Clary and Jonathan Watt reported memory safety issues which affected Thunderbird 5.

String crash using WebGL shaders

Impact: Critical
Description: Michael Jordon of Context IS reported that an overly long shader program could cause a buffer overrun and crash in a string class used to store the shader source code.


Heap overflow in ANGLE library

Impact: Critical
Description: Michael Jordon of Context IS reported a potentially exploitable heap overflow in the ANGLE library used by Mozilla's WebGL implementation.


Crash in SVGTextElement.getCharNumAtPosition()

Impact: Critical
Description: Security researcher regenrecht reported via TippingPoint's Zero Day Initiative that a SVG text manipulation routine contained a dangling pointer vulnerability.


Cross-origin data theft using canvas and Windows D2D

Impact: High
Description: nasalislarvatus3000 reported that when using Windows D2D hardware acceleration, image data from one domain could be inserted into a canvas and read by a different domain.