Description
Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
Affected products
mozilla: thunderbird
References4
- www.mozilla.org/security/advisories/mfsa2026-86/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-87/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-88/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2061087 Permissions Required
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 0% percentile: 25 · as of 8 November 2026
- CWE
- CWE-457
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