CVE-2026-74979: Vulnerability in Mozilla Firefox
Mitigation bypass in the Add-ons Manager component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.
AI Analysis
Technical Summary
The vulnerability identified as CVE-2026-74979 involves a mitigation bypass in the Add-ons Manager component of Mozilla Firefox. This flaw could potentially allow bypassing security mitigations related to add-on management. Mozilla fixed this vulnerability in Firefox 154 and Firefox ESR 153.1 as part of a broader security update that addressed multiple high, moderate, and low impact vulnerabilities across various Firefox components.
Potential Impact
The impact of CVE-2026-74979 is rated low by Mozilla. It involves a mitigation bypass which could theoretically reduce the effectiveness of security controls in the Add-ons Manager, but no known exploits in the wild have been reported. The vulnerability was fixed in official Firefox releases, mitigating any risk to users who have updated.
Mitigation Recommendations
Users and administrators should update Mozilla Firefox to version 154 or later, or Firefox ESR to version 153.1 or later, to remediate this vulnerability. Mozilla has provided official fixes in these versions. No additional mitigation steps are required beyond applying these updates.
CVE-2026-74979: Vulnerability in Mozilla Firefox
Description
Mitigation bypass in the Add-ons Manager component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.
CVSS v3.1
Score 9.8critical
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability identified as CVE-2026-74979 involves a mitigation bypass in the Add-ons Manager component of Mozilla Firefox. This flaw could potentially allow bypassing security mitigations related to add-on management. Mozilla fixed this vulnerability in Firefox 154 and Firefox ESR 153.1 as part of a broader security update that addressed multiple high, moderate, and low impact vulnerabilities across various Firefox components.
Potential Impact
The impact of CVE-2026-74979 is rated low by Mozilla. It involves a mitigation bypass which could theoretically reduce the effectiveness of security controls in the Add-ons Manager, but no known exploits in the wild have been reported. The vulnerability was fixed in official Firefox releases, mitigating any risk to users who have updated.
Mitigation Recommendations
Users and administrators should update Mozilla Firefox to version 154 or later, or Firefox ESR to version 153.1 or later, to remediate this vulnerability. Mozilla has provided official fixes in these versions. No additional mitigation steps are required beyond applying these updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-08-17T11:59:04.235Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-74/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-77/","vendor":"Mozilla"}]
Threat ID: 6a84550bc6e8be03323676b8
Added to database: 08/18/2026, 12:50:19 UTC
Last enriched: 08/18/2026, 13:25:20 UTC
Last updated: 08/19/2026, 04:30:41 UTC
Views: 7
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