<code>NSSToken</code> objects were referenced via direct points, and could have been accessed in an unsafe way on different threads, leading to a use-after-free and potentially exploitable crash. This vulnerability affects Thunderbird < 91.8, Firefox < 99, and Firefox ESR < 91.8.
https://www.mozilla.org/security/advisories/mfsa2022-15/
https://www.mozilla.org/security/advisories/mfsa2022-14/