VULNERABILITY INTELLIGENCE

CVE-2026-84639

CVSS score9.1 CRITICAL
EPSS probability0.32%
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:H

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.

Weakness classification

  • 134c704f-9b21-4f2e-91b3-4a467353bcc0: CWE-457

Primary references