CVE-2026-92015: Vulnerability in Mozilla Firefox
Privilege escalation in the WebExtensions 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-2026-92015 is a security vulnerability in the WebExtensions component of Mozilla Firefox that allows privilege escalation. The flaw was reported by Quy Pham and is classified as high impact. Mozilla addressed this vulnerability in Firefox 156 and Firefox ESR 115.41, 140.16, and 153.3. The vendor advisories confirm the fix and provide references to the bug report (Bug 2060235). No CVSS score is provided, but the impact is considered high by Mozilla.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escalate privileges within the Firefox browser, potentially leading to unauthorized actions or access beyond normal user permissions. The vulnerability affects the WebExtensions component, which is critical for browser extension security.
Mitigation Recommendations
Users and administrators should update to Firefox 156 or later, or Firefox ESR versions 115.41, 140.16, or 153.3 or later, where this vulnerability has been fixed. Mozilla has officially released patches for this issue. Applying these updates will mitigate the risk of exploitation.
CVE-2026-92015: Vulnerability in Mozilla Firefox
Description
Privilege escalation in the WebExtensions 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.
CVSS v3.1
Score 8.8high
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-92015 is a security vulnerability in the WebExtensions component of Mozilla Firefox that allows privilege escalation. The flaw was reported by Quy Pham and is classified as high impact. Mozilla addressed this vulnerability in Firefox 156 and Firefox ESR 115.41, 140.16, and 153.3. The vendor advisories confirm the fix and provide references to the bug report (Bug 2060235). No CVSS score is provided, but the impact is considered high by Mozilla.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escalate privileges within the Firefox browser, potentially leading to unauthorized actions or access beyond normal user permissions. The vulnerability affects the WebExtensions component, which is critical for browser extension security.
Mitigation Recommendations
Users and administrators should update to Firefox 156 or later, or Firefox ESR versions 115.41, 140.16, or 153.3 or later, where this vulnerability has been fixed. Mozilla has officially released patches for this issue. Applying these updates will mitigate the risk of exploitation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-15T12:33:34.461Z
- 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: 6aa93e6055bf5e2cf5d30fd9
Added to database: 09/15/2026, 12:47:28 UTC
Last enriched: 09/15/2026, 13:32:50 UTC
Last updated: 09/15/2026, 22:11:29 UTC
Views: 11
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