Privilege Escalation in Firefox Enterprise Policies Component
CVE-2026-8957

8.8HIGH

Key Information:

Vendor

Mozilla
Status
Firefox
Thunderbird
Vendor
CVE Published:
19 May 2026

What is CVE-2026-8957?

This vulnerability exists within the Enterprise Policies component of Firefox, allowing unauthorized users to escalate privileges. This security flaw may enable a malicious actor to gain elevated access, compromising system integrity and user data. The issue has been addressed in the latest versions of Firefox, specifically Firefox 151 and Firefox ESR 140.11, where adequate security measures have been implemented to mitigate this risk effectively.

Affected Version(s)

Firefox 140.11

Firefox 151

Thunderbird 140.11

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2033850
https://www.mozilla.org/security/advisories/mfsa2026-46/
https://www.mozilla.org/security/advisories/mfsa2026-48/

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Mateusz Dobrzyński
.