CVE-2026-84640
One byte overflow read in mail parser
Description
A maliciously constructed mail header could lead to a one byte read past the end of a buffer. 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:NAvailabilityNone
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=2063964
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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