Mozilla: Use-after-free of nsLanguageAtomService object

During process shutdown, a document could have caused a use-after-free of a languages service object, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox 93, Thunderbird 91.2, and Firefox ESR 91.2...

Mozilla: Validation message could have been overlaid on another origin

Through use of reportValidity and window.open, a plain-text validation message could have been overlaid on another origin, leading to possible user confusion and spoofing attacks. This vulnerability affects Firefox 93, Thunderbird 91.2, and Firefox ESR 91.2...