CVE-2026-84639
Uninitialized memory in MIME parsing
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.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:HConfidentialityHigh
I:NIntegrityNone
A:HAvailabilityHigh
Weaknesses
Affected Products
Mozilla
oss-project·USaka mozilla corp.
and 1 more affected products View all →
Exploitability
Official Patch Available
References
https://bugzilla.mozilla.org/show_bug.cgi?id=2061087
bugzilla.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-86/
mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-87/
mozilla.org
and 1 more references View all →
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