Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
CVE-2026-8957
HIGHNVD 8.86.5▼
EchelonGraph scoreHIGH confidence
Score 6.5 from GitHub Security Advisory published 2026-05-19. NVD baseline CVSS 6.5; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, nvd
8.8
- CVSS v3
- 8.8
- EG Score
- 6.5(high)
- EPSS
- 12.5%
- KEV
- Not listed
Published
May 19, 2026
Last Modified
May 20, 2026
References (5)
- security@mozillahttps://bugzilla.mozilla.org/show_bug.cgi?id=2033850
- security@mozillahttps://www.mozilla.org/security/advisories/mfsa2026-46/
- security@mozillahttps://www.mozilla.org/security/advisories/mfsa2026-48/
- security@mozillahttps://www.mozilla.org/security/advisories/mfsa2026-50/
- security@mozillahttps://www.mozilla.org/security/advisories/mfsa2026-51/
Frequently asked(5)
What is CVE-2026-8957?
CVE-2026-8957 is a high vulnerability published on May 19, 2026. Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
When was CVE-2026-8957 disclosed?
CVE-2026-8957 was first published in the National Vulnerability Database on May 19, 2026, with the most recent update on May 20, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-8957 actively exploited?
CVE-2026-8957 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 12.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-8957?
CVE-2026-8957 has a CVSS v3 base score of 8.8 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 6.5.
How do I remediate CVE-2026-8957?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-8957, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-8957
Is Your Infrastructure Affected by CVE-2026-8957?
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