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 updated packages for Thunderbird and Firefox ESR versions that address these vulnerabilities. Users should apply the security updates as provided in Red Hat Enterprise Linux 8 and related distributions. Detailed update instructions are available in the Red Hat advisory at https://access.redhat.com/articles/11258. Since official fixes are available, applying these updates is the recommended mitigation. No additional vendor advisory indicates that no action is required or that the issues are already mitigated.
Description
Multiple security vulnerabilities affecting Mozilla Thunderbird and 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 disclosure, mitigation bypasses, and same-origin policy bypasses. The fixes are included in updated versions of Thunderbird ESR 140.8, Firefox ESR 115.33, Firefox ESR 140.8, Firefox 148, and Thunderbird 148. The advisory covers a broad range of components such as the JavaScript engine, DOM, Audio/Video, Graphics, Networking, and Storage subsystems.
References
- access.redhat.com/errata/RHSA-2026:3515 (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)