Red Hat Security Advisory: thunderbird security update
Affects Red Hat thunderbirdSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 9.8 Critical : upgrade the Red Hat redhat/thunderbird package to 140.4 as a priority.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 140.4
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 14 Oct 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
Upgrade the Red Hat redhat/thunderbird package to 140.4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Red Hatredhat/thunderbirdpkg:rpm/redhat/thunderbirdOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released updated Thunderbird packages for Red Hat Enterprise Linux 8.8 variants that address these vulnerabilities. Users should apply the security update as provided by Red Hat to remediate these issues. For detailed update instructions, refer to the Red Hat article at https://access.redhat.com/articles/11258. Since official fixes are available, applying the update is the recommended mitigation.
Description
Multiple security vulnerabilities affecting Mozilla Thunderbird have been addressed in a Red Hat security advisory. These include memory safety bugs, out-of-bounds read/write issues, use-after-free conditions, cross-process information leaks, and improper handling of OBJECT tag attributes. The vulnerabilities are related to Firefox components integrated within Thunderbird and affect versions prior to Thunderbird ESR 140.4 and Thunderbird 144. Red Hat has released updated packages for Red Hat Enterprise Linux 8.8 variants to fix these issues.
References
- access.redhat.com/errata/RHSA-2025:19942 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403763 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403765 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403768 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403769 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403770 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403774 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403776 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2025/rhsa-2025_19942.json (opens in a new tab)