Mozilla blocked compromised intermediate eMudhra certificates via OneCRL on the 17th of October which was distributed to clients via RemoteSettings the same day. This update contains the updated OneCRL block list, ensuring clients will block the compromised certificates even if RemoteSettings is disabled by policy or otherwise unavailable in the user's network environment. This vulnerability was fixed in Firefox 158.0.1, Firefox ESR 153.5.1, Firefox ESR 115.43.1, Thunderbird 158.0.1, and Thunderbird 153.5.1.
https://www.mozilla.org/security/advisories/mfsa2026-115/
https://www.mozilla.org/security/advisories/mfsa2026-114/
https://www.mozilla.org/security/advisories/mfsa2026-113/
https://www.mozilla.org/security/advisories/mfsa2026-112/
https://www.mozilla.org/security/advisories/mfsa2026-111/
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-104991