CVE-2026-16382: Vulnerability in Mozilla Firefox
CVE-2026-16382 is a mitigation bypass vulnerability in the DOM Service Workers component of Mozilla Firefox. It affects Firefox versions prior to 153 and was fixed in Firefox 153. The vulnerability has a critical CVSS score of 9.8, indicating high impact on confidentiality, integrity, and availability. The vendor advisory confirms the fix is included in Firefox 153. No known exploits in the wild have been reported. This issue is part of a broader set of security fixes released in Firefox 153 and Thunderbird 153.
AI Analysis
Technical Summary
CVE-2026-16382 is a mitigation bypass vulnerability located in the DOM Service Workers component of Mozilla Firefox. This vulnerability allows bypassing security mitigations designed to protect the browser environment. It was addressed and fixed in Firefox version 153. The vulnerability has a CVSS 3.1 base score of 9.8, reflecting network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. The Mozilla Foundation Security Advisory MFSA2026-68 confirms the fix and includes this vulnerability among multiple high-impact issues resolved in Firefox 153.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to bypass security mitigations in the Service Workers component, potentially leading to full compromise of confidentiality, integrity, and availability of the affected Firefox browser. Given the critical CVSS score of 9.8, the impact is severe. However, no known exploits in the wild have been reported at this time.
Mitigation Recommendations
This vulnerability is fixed in Mozilla Firefox version 153. Users and administrators should update affected Firefox installations to version 153 or later to remediate this issue. Since this is not a cloud service, manual patching is required. There are no vendor advisories indicating that no action is required or that the issue is already mitigated without patching.
CVE-2026-16382: Vulnerability in Mozilla Firefox
Description
CVE-2026-16382 is a mitigation bypass vulnerability in the DOM Service Workers component of Mozilla Firefox. It affects Firefox versions prior to 153 and was fixed in Firefox 153. The vulnerability has a critical CVSS score of 9.8, indicating high impact on confidentiality, integrity, and availability. The vendor advisory confirms the fix is included in Firefox 153. No known exploits in the wild have been reported. This issue is part of a broader set of security fixes released in Firefox 153 and Thunderbird 153.
CVSS v3.1
Score 9.8critical
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16382 is a mitigation bypass vulnerability located in the DOM Service Workers component of Mozilla Firefox. This vulnerability allows bypassing security mitigations designed to protect the browser environment. It was addressed and fixed in Firefox version 153. The vulnerability has a CVSS 3.1 base score of 9.8, reflecting network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. The Mozilla Foundation Security Advisory MFSA2026-68 confirms the fix and includes this vulnerability among multiple high-impact issues resolved in Firefox 153.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to bypass security mitigations in the Service Workers component, potentially leading to full compromise of confidentiality, integrity, and availability of the affected Firefox browser. Given the critical CVSS score of 9.8, the impact is severe. However, no known exploits in the wild have been reported at this time.
Mitigation Recommendations
This vulnerability is fixed in Mozilla Firefox version 153. Users and administrators should update affected Firefox installations to version 153 or later to remediate this issue. Since this is not a cloud service, manual patching is required. There are no vendor advisories indicating that no action is required or that the issue is already mitigated without patching.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-07-20T21:56:53.743Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"}]
Threat ID: 6a5f6cbe2a4a8d59892625f0
Added to database: 07/21/2026, 12:57:34 UTC
Last enriched: 07/30/2026, 10:37:35 UTC
Last updated: 09/04/2026, 01:21:27 UTC
Views: 69
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