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, 23:04 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 in Red Hat Enterprise Linux 9 and related variants. 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 mitigations are specified beyond applying the provided patches.
Description
A security update for Mozilla Thunderbird and related Firefox components addresses multiple vulnerabilities including heap buffer overflows, use-after-free bugs, integer overflows, sandbox escapes, privilege escalations, information disclosures, and mitigation bypasses. These issues affect various components such as the JavaScript engine, DOM, Audio/Video, Networking, Graphics, and Storage. The update is rated as important by Red Hat and fixes these vulnerabilities in Thunderbird ESR 140.8, Firefox ESR 140.8, Firefox 148, and Thunderbird 148.
References
- access.redhat.com/errata/RHSA-2026:3516 (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)