# CVE-2026-124939: JIT miscompilation in the JavaScript Engine: JIT component

Status: published. Published: 2026-11-10. Updated: 2026-11-10.

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Mozilla / Firefox: ≥ 153.7; ≤ 153.* (unaffected, rpm); ≥ 160; ≤ * (unaffected, rpm). Source: CNA: mozilla

## Severity and prioritization

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: Not reported

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://bugzilla.mozilla.org/show_bug.cgi?id=2076663 (CNA: mozilla)

- https://www.mozilla.org/security/advisories/mfsa2026-125/ (CNA: mozilla)

- https://www.mozilla.org/security/advisories/mfsa2026-127/ (CNA: mozilla)

## Provenance

- CNA: mozilla: https://www.cve.org/CVERecord?id=CVE-2026-124939; retrieved 2026-11-10; source updated 2026-11-10

Revision: 4c0567451e3774e3535f843f54191121ffc5b49df41231502bceb669f51141da

Canonical: https://y2.dev/cve/CVE-2026-124939

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