According to an advisory from the open-source group, 8 of the 10 vulnerabilities are rated "critical," meaning that they can be used to run attacker code and install software, requiring no user interaction beyond normal browsing.
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.
Mozilla also credited researcher Michael Jordon of Context IS with reporting a pair of critical issues -- that an overly long shader program could cause a buffer overrun and crash in a string class used to store the shader source code; and a potentially exploitable heap overflow in the ANGLE library used by Mozilla's WebGL implementation.
Some additional security problems fixed:
- Security researcher regenrecht reported via TippingPoint's Zero Day Initiative that a SVG text manipulation routine contained a dangling pointer vulnerability.
- 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.
- 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.