Red Hat Security Advisory: thunderbird security update
Affects Red Hat thunderbirdSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 7.5 High.
Data as of 26 Oct 2026, 11:07 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 15% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Nov 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
AI-suggested
Red Hat has released updated Thunderbird packages for Red Hat Enterprise Linux 9 and its Extended Update Support versions that address these vulnerabilities. Users should apply the provided security update as detailed in the Red Hat advisory RHSA-2025:21842. For update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the official update.
Description
Multiple security vulnerabilities affecting Mozilla Thunderbird, as packaged by Red Hat, have been addressed in a security update. These include issues such as race conditions, use-after-free, mitigation bypasses, same-origin policy bypasses, and spoofing vulnerabilities in various Firefox components integrated into Thunderbird. The update is rated as important by Red Hat Product Security and affects Red Hat Enterprise Linux 9 and its Extended Update Support versions. The advisory references nine CVEs related to Firefox components used by Thunderbird. No CVSS scores are provided in the advisory.
References
- access.redhat.com/errata/RHSA-2025:21842 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2414079 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2414080 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2414083 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2414084 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2414085 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2414086 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2414090 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2414091 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2414092 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2025/rhsa-2025_21842.json (opens in a new tab)