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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

CVE-2026-16394 is a mitigation bypass vulnerability in the DOM security component of Mozilla Firefox. This vulnerability was addressed and fixed in Firefox version 153. It has a high CVSS score of 9.1, indicating critical severity with high impact on confidentiality and integrity. The issue affects all Firefox versions prior to 153. The vendor advisory confirms the fix is included in Firefox 153. There are no known exploits in the wild at this time.

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: 07/30/2026, 10:07:45 UTC

Technical Analysis

CVE-2026-16394 is a vulnerability in Mozilla Firefox's DOM security component that allows bypassing mitigation controls. This flaw was resolved in Firefox 153. The vulnerability has a CVSS v3.1 base score of 9.1 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N), indicating it is remotely exploitable without privileges or user interaction and can lead to high confidentiality and integrity impacts. The vendor advisory from Mozilla confirms the fix was released in Firefox 153. No active exploitation has been reported.

Potential Impact

Successful exploitation of this vulnerability could allow an attacker to bypass security mitigations in the DOM security component, potentially leading to unauthorized access to sensitive information and modification of data within the affected Firefox browser. The impact is rated high, affecting confidentiality and integrity, but not availability.

Mitigation Recommendations

Mozilla has released an official fix for this vulnerability in Firefox version 153. Users and administrators should update to Firefox 153 or later to remediate this issue. No additional mitigations are required once the update is applied.

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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: 07/30/2026, 10:07:45 UTC

Last updated: 08/31/2026, 22:52:08 UTC

Views: 64

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