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CVE-2026-16394: Vulnerability in Mozilla Firefox

0
Critical
VulnerabilityCVE-2026-16394cvecve-2026-16394
Published: 07/21/2026 (07/21/2026, 12:38:08 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 153.

CVSS v3.1

Score 9.1critical

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Affected software

GitHub Actionsmore threats →ai
mozilla/firefox
pkg:github/mozilla/firefox
Affected versions
<153

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 07/21/2026, 13:14:54 UTC

Technical Analysis

CVE-2026-16394 is a mitigation bypass vulnerability affecting the DOM security component in Mozilla Firefox. The vulnerability was publicly disclosed and fixed in Firefox 153 as part of a security advisory (MFSA2026-68) that addressed numerous security issues. The vendor advisory categorizes this vulnerability as having moderate impact. No detailed technical exploitation methods or attack vectors are provided in the advisory. The fix is included in Firefox 153, indicating that versions prior to 153 are affected.

Potential Impact

The vulnerability allows bypassing security mitigations within the DOM security component, which could potentially weaken the browser's security posture. The vendor rates the impact as moderate. There are no reports of active exploitation in the wild. The overall risk is mitigated by the availability of the fix in Firefox 153.

Mitigation Recommendations

Users and administrators should upgrade to Mozilla Firefox version 153 or later to remediate this vulnerability. Mozilla has officially fixed this issue in Firefox 153 as part of their security advisory MFSA2026-68. No additional mitigation actions are required beyond applying the official update.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-07-20T21:57:19.701Z
Cvss Version
null
State
PUBLISHED
Remediation Level
null
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"}]

Threat ID: 6a5f6cc12a4a8d598926291f

Added to database: 07/21/2026, 12:57:37 UTC

Last enriched: 07/21/2026, 13:14:54 UTC

Last updated: 07/21/2026, 21:09:47 UTC

Views: 4

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