# CVE-2026-92057: Mozilla Firefox mitigation bypass in Enterprise Policies component

Source: https://junglewise.ai/threats/cve-2026-92057-mozilla-firefox-mitigation-bypass-in-enterprise-policies  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-15. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-92057 · Severity: critical · CVSS 9.1 · Published 2026-09-15

Firefox and Thunderbird include an Enterprise Policies component used to enforce security and configuration controls in corporate environments. A mitigation bypass vulnerability in this component could allow an attacker to circumvent critical security protections, potentially leading to unauthorized access or malicious code execution on managed systems.

Technologies: [Mozilla Firefox](https://junglewise.ai/threats/technologies/firefox), [Mozilla Firefox ESR](https://junglewise.ai/threats/technologies/firefox-esr), [Mozilla Thunderbird](https://junglewise.ai/threats/technologies/thunderbird), [Mozilla Thunderbird ESR](https://junglewise.ai/threats/technologies/thunderbird-esr). Vendors: [Mozilla](https://junglewise.ai/threats/vendors/mozilla).

## Quick answers

**Is CVE-2026-92057 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-92057 being exploited in the wild.

**How severe is CVE-2026-92057?** Critical severity, with a CVSS score of 9.1, published 15 September 2026.

**Which products and versions are affected?** Mozilla Firefox before 156; Mozilla Firefox ESR before 153.3; Mozilla Thunderbird before 156; Mozilla Thunderbird ESR before 153.3.

**Is there a fix for CVE-2026-92057?** A patch was published on 2026-09-15: Fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird ESR 153.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-92057 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-92057?** Check whether you run Mozilla Firefox, Mozilla Firefox ESR, Mozilla Thunderbird or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

CVE-2026-92057 is a mitigation bypass vulnerability in the Enterprise Policies component of Mozilla Firefox and Thunderbird. The vulnerability allows an attacker to circumvent security protections or controls that are enforced through the Enterprise Policies mechanism, which is designed to apply centralized security policies in managed deployments. The attack vector appears to be network-based, potentially exploitable remotely without requiring user interaction or authentication. Successful exploitation could allow an attacker to disable or bypass critical security mitigations, leading to privilege escalation or further compromise of the affected system. The vulnerability has been patched in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird ESR 153.3.

## Affected products

- Mozilla Firefox before 156
- Mozilla Firefox ESR before 153.3
- Mozilla Thunderbird before 156
- Mozilla Thunderbird ESR before 153.3

## Timeline

- 2026-09-15: disclosed: CVE-2026-92057 publicly disclosed
- 2026-09-15: patched: Fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird ESR 153.3

## References

- [https://bugzilla.mozilla.org/show_bug.cgi?id=2065646](https://bugzilla.mozilla.org/show_bug.cgi?id=2065646)
- [https://www.mozilla.org/security/advisories/mfsa2026-90/](https://www.mozilla.org/security/advisories/mfsa2026-90/)

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