Vulnerabilities

A redirected HTTP request which is observed or modified through a web extension could bypass existing CORS checks, leading to potential disclosure of cross-origin information.

When in an endless loop, a website specifying a custom cursor using CSS could make it look like the user is interacting with the user interface, when they are not.

An iframe sandbox element with the allow-popups flag could be bypassed when using noopener links.

By observing the stack trace for JavaScript errors in web workers, it was possible to leak the result of a cross-origin redirect.

Mozilla developers and community members reported memory safety bugs present in Firefox 78 and Firefox ESR 78.0.

The code for downloading files did not properly take care of special characters, which led to an attacker being able to cut off the file ending at an earlier position, leading to a different file type being downloaded th…

Firefox could be made to load attacker-supplied DLL files from the installation directory.

JIT optimizations involving the Javascript arguments object could confuse later optimizations.