Description
Internally found bugs present in Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.
Affected products
mozilla: firefox; mozilla: thunderbird
References7
- www.mozilla.org/security/advisories/mfsa2026-74/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-77/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-78/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-80/ Vendor Advisory
- bugzilla.mozilla.org/buglist.cgi?bug_id=2018164%2C2045404%2C204… Not Applicable
- bugzilla.mozilla.org/buglist.cgi?bug_id=2045796%2C2046734%2C205… Not Applicable
- bugzilla.mozilla.org/buglist.cgi?bug_id=2053153%2C2053262%2C205… Not Applicable
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 50 · as of 11 November 2026
- CWE
- CWE-119
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