cve.bz

CVE-2026-84143

9.8 criticalEPSS 0.4%

Critical (9.8) in mozilla. EPSS 0.4% chance of exploitation in the next 30 days.

Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. 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 155, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.

Severity

CVSS 3.1

9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.4% chance of exploitation in the next 30 days; higher than 31% of CVEs (scores of 2026-10-31)
CWEs
CWE-119, CWE-200
Published
Modified
Record from
the NVD, synced

Affected

References

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