Return registers were overwritten which could have allowed an attacker to execute arbitrary code. *Note:* This issue only affected Armv7-A systems. Other operating systems are unaffected. This vulnerability affects Firefox < 124, Firefox ESR < 115.9, and Thunderbird < 115.9.
https://www.mozilla.org/security/advisories/mfsa2024-14/
https://www.mozilla.org/security/advisories/mfsa2024-13/
https://www.mozilla.org/security/advisories/mfsa2024-12/
https://lists.debian.org/debian-lts-announce/2024/03/msg00028.html
https://lists.debian.org/debian-lts-announce/2024/03/msg00022.html