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Mozilla Foundation Security Advisory 2011-29

Security issues addressed in Firefox 6

Announced
August 16, 2011
Impact
Critical
Products
Firefox
Fixed in
  • Firefox 6

Miscellaneous memory safety hazards (rv:4.0)

Impact: Critical
Description: Mozilla identified and fixed several memory safety bugs in the browser engine used in Firefox 4, Firefox 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.

References:

Aral Yaman reported a WebGL crash which affected Firefox 4 and Firefox 5.

Vivekanand Bolajwar reported a JavaScript crash which affected Firefox 4 and Firefox 5.

Bert Hubert and Theo Snelleman of Fox-IT reported a crash in the Ogg reader which affected Firefox 4 and Firefox 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 Firefox 4 and Firefox 5.

Unsigned scripts can call script inside signed JAR

Impact: Critical
Description: Rafael Gieschke reported that unsigned JavaScript could call into script inside a signed JAR thereby inheriting the identity of the site that signed the JAR as well as any permissions that a user had granted the signed JAR.

This is a distinct issue from MFSA 2008-23 and did not affect Firefox 3.6.

References:

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.

References:

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.

References:

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.

References:

Credential leakage using Content Security Policy reports

Impact: High
Description: Mike Cardwell reported that Content Security Policy violation reports failed to strip out proxy authorization credentials from the list of request headers. Daniel Veditz reported that redirecting to a website with Content Security Policy resulted in the incorrect resolution of hosts in the constructed policy.

References:

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.

References: