Red Hat Security Advisory: thunderbird security update
Affects Red Hat thunderbirdSource GCVE Database
Not known to be exploited · CVSS 8.8 High.
Data as of 5 Nov 2026, 23:03 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 Feb 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 5 Nov 2026.
What to do
AI-suggested
Red Hat has released security updates for Thunderbird and Firefox components as part of Red Hat Enterprise Linux 9.4 Extended Update Support. Users should apply these official updates promptly to remediate the vulnerabilities. Detailed update instructions are available in the Red Hat advisory at https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the provided patches.
Description
Multiple security vulnerabilities affecting Mozilla Thunderbird and related Firefox components have been addressed in a Red Hat security advisory. These include heap buffer overflows, use-after-free bugs, integer overflows, sandbox escapes, privilege escalations, information disclosures, and mitigation bypasses. The fixes are included in updates for Thunderbird ESR 140.8, Firefox ESR 140.8, Firefox 148, and Thunderbird 148. The advisory covers Red Hat Enterprise Linux 9.4 Extended Update Support and related variants.
References
- access.redhat.com/errata/RHSA-2026:3981 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2440219 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442284 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442287 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442288 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442290 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442291 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442292 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442294 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442295 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442297 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442298 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442300 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442302 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442304 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442307 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442308 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442309 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442312 (opens in a new tab)