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EPSS 0.3%top 74%

CVE-2026-16402: Vulnerability in Mozilla Firefox

0
Critical
VulnerabilityCVE-2026-16402cvecve-2026-16402
Published: 07/21/2026 (07/21/2026, 12:38:14 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

CVE-2026-16402 is an integer overflow vulnerability in the Graphics: ImageLib component of Mozilla Firefox. This vulnerability was fixed in Firefox version 153. It has a critical CVSS score of 9.8, indicating high severity with potential for complete confidentiality, integrity, and availability impact. The vulnerability affects all Firefox versions prior to 153. Mozilla has released an official fix in Firefox 153 to address this issue.

CVSS v3.1

Score 9.8critical

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

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, 09:53:38 UTC

Technical Analysis

CVE-2026-16402 is an integer overflow vulnerability located in the Graphics: ImageLib component of Mozilla Firefox. The flaw could allow an attacker to cause memory corruption or other impacts related to integer overflow errors. This vulnerability was resolved in Firefox 153. The CVSS 3.1 base score is 9.8 (critical), with attack vector network, low attack complexity, no privileges required, no user interaction, and full impact on confidentiality, integrity, and availability. The vendor advisory confirms the fix was included in Firefox 153.

Potential Impact

The vulnerability has a critical impact, potentially allowing remote attackers to execute arbitrary code or cause denial of service due to integer overflow in the graphics library. The CVSS score of 9.8 reflects the high severity and the potential for complete compromise of confidentiality, integrity, and availability of the affected system.

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. Since this is not a cloud service, patching the client software is required to mitigate the risk.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-07-20T21:57:35.982Z
Cvss Version
null
State
PUBLISHED
Remediation Level
null
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"}]

Threat ID: 6a5f6cc22a4a8d5989262952

Added to database: 07/21/2026, 12:57:38 UTC

Last enriched: 07/30/2026, 09:53:38 UTC

Last updated: 09/04/2026, 10:52:07 UTC

Views: 58

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