# CVE-2026-124943

Use-after-free in Firefox/Thunderbird layout enabling potential remote code execution.

- Page: https://www.vulneraibility.com/cve/CVE-2026-124943
- CVSS: 8.8
- Known exploited: not in CISA KEV as of our last sync
- EPSS: 0.32% (percentile 25.0)
- CISA SSVC: exploitation none, automatable no, technical impact total (assessed 2026-11-10)
- Weakness: CWE-416
- Published: 2026-11-10

## Affected

- Mozilla Firefox < 160
- Mozilla Thunderbird < 160
- Gecko-based applications

## Impact

Potential remote code execution or crash via crafted web content exploiting layout use-after-free (CWE-416).

## Action

Immediate action required

## Recommendation

Upgrade to Firefox/Thunderbird 160+ immediately.

## References

- [other] https://bugzilla.mozilla.org/show_bug.cgi?id=2078990
- [other] https://www.mozilla.org/security/advisories/mfsa2026-125/
- [other] https://www.mozilla.org/security/advisories/mfsa2026-128/

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.