VULNERABILITY INTELLIGENCE
CVE-2026-84640
CVSS score7.5 HIGH
EPSS probability0.26%
CISA KEVNot currently listed
Published2026-09-01
Last modified2026-09-03
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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.
Weakness classification
- CWE-126: Buffer Over-read
Primary references
- security@mozilla.org — Permissions Required
- security@mozilla.org — Vendor Advisory
- security@mozilla.org — Vendor Advisory
- security@mozilla.org — Vendor Advisory