Integer overflow in the SVG component. This vulnerability affects Firefox < 143, Firefox ESR < 115.28, Firefox ESR < 140.3, Thunderbird < 143, and Thunderbird < 140.3.
https://www.mozilla.org/security/advisories/mfsa2025-78/
https://www.mozilla.org/security/advisories/mfsa2025-77/
https://www.mozilla.org/security/advisories/mfsa2025-75/
https://www.mozilla.org/security/advisories/mfsa2025-74/
https://www.mozilla.org/security/advisories/mfsa2025-73/
https://lists.debian.org/debian-lts-announce/2025/09/msg00026.html