CVE-2026-92019: Vulnerability in Mozilla Firefox
Mitigation bypass in the Remote Settings Client component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 140.16.
AI Analysis
Technical Summary
CVE-2026-92019 is a mitigation bypass vulnerability affecting the Remote Settings Client component in Mozilla Firefox. The issue allows bypassing of security mitigations, potentially undermining protections implemented in the browser. Mozilla fixed this vulnerability in Firefox 156 and Firefox ESR versions 115.41, 140.16, and 153.3 as part of their September 15, 2026 security advisories. The vulnerability is rated with high impact by Mozilla, but no active exploitation has been reported.
Potential Impact
The vulnerability enables bypassing of mitigation controls in the Remote Settings Client component, which could allow an attacker to circumvent security protections. Mozilla classifies the impact as high, indicating a significant security risk if exploited. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3. Users and administrators should apply these updates promptly to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-92019: Vulnerability in Mozilla Firefox
Description
Mitigation bypass in the Remote Settings Client component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 140.16.
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
pkg:github/mozilla/firefoxRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-92019 is a mitigation bypass vulnerability affecting the Remote Settings Client component in Mozilla Firefox. The issue allows bypassing of security mitigations, potentially undermining protections implemented in the browser. Mozilla fixed this vulnerability in Firefox 156 and Firefox ESR versions 115.41, 140.16, and 153.3 as part of their September 15, 2026 security advisories. The vulnerability is rated with high impact by Mozilla, but no active exploitation has been reported.
Potential Impact
The vulnerability enables bypassing of mitigation controls in the Remote Settings Client component, which could allow an attacker to circumvent security protections. Mozilla classifies the impact as high, indicating a significant security risk if exploited. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3. Users and administrators should apply these updates promptly to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-15T12:33:38.619Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-90/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-91/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-92/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-93/","vendor":"Mozilla"}]
Threat ID: 6aa93e6055bf5e2cf5d30fdd
Added to database: 09/15/2026, 12:47:28 UTC
Last enriched: 09/15/2026, 13:32:32 UTC
Last updated: 09/16/2026, 03:08:02 UTC
Views: 3
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