Privilege escalation in the DOM: Service Workers component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.
https://www.mozilla.org/security/advisories/mfsa2026-99/
https://www.mozilla.org/security/advisories/mfsa2026-97/
https://www.mozilla.org/security/advisories/mfsa2026-103/
https://www.mozilla.org/security/advisories/mfsa2026-102/
https://www.mozilla.org/security/advisories/mfsa2026-101/