CVE-2026-109721 Affecting thunderbird package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-UBUNTU2204-THUNDERBIRD-20975498
- published16 Oct 2026
- disclosed13 Oct 2026
Introduced: 13 Oct 2026
NewCVE-2026-109721 (opens in a new tab)How to fix?
There is no fixed version for Ubuntu:22.04 thunderbird.
NVD Description
Note: Versions mentioned in the description apply only to the upstream thunderbird package and not the thunderbird package as distributed by Ubuntu.
See How to fix? for Ubuntu:22.04 relevant fixed versions and status.
Incorrect boundary conditions in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
References
- http://people.ubuntu.com/~ubuntu-security/cve/CVE-2026-109721
- https://bugzilla.mozilla.org/show_bug.cgi?id=2074161
- https://www.mozilla.org/security/advisories/mfsa2026-106/
- https://www.mozilla.org/security/advisories/mfsa2026-108/
- https://www.mozilla.org/security/advisories/mfsa2026-109/
- https://www.mozilla.org/security/advisories/mfsa2026-110/