Out-of-bounds Write The advisory has been revoked - it doesn't affect any version of package thunderbird (opens in a new tab)
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-RHEL10-THUNDERBIRD-15769832
- published26 Mar 2026
- disclosed24 Mar 2026
Introduced: 24 Mar 2026
CVE-2026-4699 (opens in a new tab)Amendment
The Red Hat security team deemed this advisory irrelevant for RHEL:10.
NVD Description
Note: Versions mentioned in the description apply only to the upstream thunderbird package and not the thunderbird package as distributed by RHEL.
Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
References
- https://bugzilla.redhat.com/show_bug.cgi?id=2450739
- https://access.redhat.com/security/cve/CVE-2026-4699
- https://access.redhat.com/errata/RHSA-2026:5931
- https://access.redhat.com/errata/RHSA-2026:6342
- https://access.redhat.com/errata/RHSA-2026:7843
- https://access.redhat.com/errata/RHSA-2026:8315
- https://bugzilla.mozilla.org/show_bug.cgi?id=2021863
- https://www.mozilla.org/security/advisories/mfsa2026-20/
- https://www.mozilla.org/security/advisories/mfsa2026-21/
- https://www.mozilla.org/security/advisories/mfsa2026-22/
- https://www.mozilla.org/security/advisories/mfsa2026-23/
- https://www.mozilla.org/security/advisories/mfsa2026-24/