Thunderbird 155, Thunderbird ESR · Internally Found Bugs Fixed
Affects MicrosoftSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical.
Data as of 14 Nov 2026, 10:01 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 1 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
AI-suggested
Since the vulnerability is marked as fixed in Thunderbird versions 155, ESR 153.2, and ESR 140.15, users should ensure they are running these or later versions.
Description
This entry reports internally found bugs fixed in Thunderbird versions 155, Thunderbird ESR 153.2, and Thunderbird ESR 140.15. The vulnerability is identified as CVE-2026-84143 and is associated with Microsoft products. The description references the Microsoft Support Lifecycle for software support details but does not provide specific technical details or impact information about the vulnerability itself.