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EPSS 0.4%top 65%

CVE-2026-16400: Vulnerability in Mozilla Firefox

0
High
Published: 07/21/2026 (07/21/2026, 12:38:13 UTC)
Source: GCVE Database
Vendor/Project: Mozilla
Product: Firefox

Description

Information disclosure in the DOM: Security component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

CVSS v3.1

Score 7.5high

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

Affected software

Affected versions
<153

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 07/22/2026, 17:40:52 UTC

Technical Analysis

CVE-2026-16400 is an information disclosure vulnerability affecting the DOM Security component in Firefox. The flaw could allow unauthorized disclosure of information via the DOM. Mozilla fixed this vulnerability in Firefox 153 as part of a security update addressing multiple high and moderate impact issues. There is no CVSS score provided, and no known active exploitation has been reported. The vendor advisory confirms the fix and categorizes the impact as moderate.

Potential Impact

The vulnerability could lead to unauthorized disclosure of information through the DOM Security component in Firefox. This may expose sensitive data to attackers under certain conditions. However, no known exploits in the wild have been reported, and the issue is mitigated by updating to Firefox 153.

Mitigation Recommendations

Users and administrators should update Firefox to version 153 or later to remediate this vulnerability. The vendor advisory confirms that the issue is fixed in Firefox 153. No additional mitigation steps are required once the update is applied.

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Technical Details

Gcve Source
db.gcve.eu
Osv Id
GHSA-573v-jgf3-jx4p
Osv Schema Version
1.4.0
Aliases
["CVE-2026-16400"]
Ecosystems
[]
Database Specific Severity
null
Cvss Version
null

Threat ID: 6a5fd1561010f89cc21c9971

Added to database: 07/21/2026, 20:06:46 UTC

Last enriched: 07/22/2026, 17:40:52 UTC

Last updated: 09/02/2026, 10:52:07 UTC

Views: 38

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