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CVE-2026-16408: Vulnerability in Mozilla Firefox

0
Critical
VulnerabilityCVE-2026-16408cvecve-2026-16408
Published: 07/21/2026 (07/21/2026, 12:38:19 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

CVE-2026-16408 is a critical integer overflow vulnerability in the Audio/Video Playback component of Mozilla Firefox. This flaw allows an attacker to cause severe impacts including full confidentiality, integrity, and availability compromise. The vulnerability affects Firefox versions prior to 153 and was fixed in Firefox 153. No known exploits are reported in the wild. The issue is part of a broader set of high-impact vulnerabilities addressed in Firefox 153 and Thunderbird 153.

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, 09:52:35 UTC

Technical Analysis

An integer overflow vulnerability exists in the Audio/Video Playback component of Mozilla Firefox, identified as CVE-2026-16408. This vulnerability was resolved in Firefox 153. The flaw could allow an attacker to execute actions leading to complete compromise of confidentiality, integrity, and availability of the affected system. The CVSS v3.1 base score is 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges required, no user interaction, and impacts to confidentiality, integrity, and availability. The vendor advisory confirms the fix in Firefox 153 and Thunderbird 153 and lists this vulnerability among multiple high-impact issues addressed in these releases.

Potential Impact

Successful exploitation of this integer overflow vulnerability can result in full compromise of confidentiality, integrity, and availability of the affected Firefox browser. This means attackers could potentially execute arbitrary code, cause crashes, or bypass security controls leading to severe system impact. However, no known exploits are currently reported in the wild.

Mitigation Recommendations

Mozilla has released an official fix for this vulnerability in Firefox 153. Users and administrators should update affected Firefox installations to version 153 or later to remediate this issue. For Thunderbird users, updating to Thunderbird 153 or later also addresses this vulnerability. No additional mitigations are specified by the vendor advisory.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-07-20T21:57:48.225Z
Cvss Version
null
State
PUBLISHED
Remediation Level
null
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"}]

Threat ID: 6a5f6cc22a4a8d598926296b

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

Last enriched: 07/30/2026, 09:52:35 UTC

Last updated: 09/02/2026, 15:04:05 UTC

Views: 68

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