By misusing a race in our notification code, an attacker could have forcefully hidden the notification for pages that had received full screen and pointer lock access, which could have been used for spoofing attacks.
Thunderbird unexpectedly enabled JavaScript in the composition area.
The JavaScript execution context was limited to this area and did not
receive chrome-level privileges, but could be used as a stepping stone
to further an attack with other vulnerabilities.
Failure to correctly record the location of live pointers across wasm instance calls resulted in a GC occurring within the call not tracing those live pointers. This could have led to a use-after-free causing a potentially exploitable crash.
Mozilla developers and community members Julian Hector, Randell Jesup, Gabriele Svelto, Tyson Smith, Christian Holler, and Masayuki Nakano reported memory safety bugs present in Firefox 94. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.