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EPSS 0.4%top 64%

CVE-2026-16369: Vulnerability in Mozilla Firefox

0
Critical
Published: 07/21/2026 (07/21/2026, 12:37:42 UTC)
Source: GCVE Database
Vendor/Project: Mozilla
Product: Firefox

Description

Integer overflow in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

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

Affected versions
<153<140.13

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 07/22/2026, 17:39:51 UTC

Technical Analysis

CVE-2026-16369 describes an integer overflow vulnerability in the JavaScript: WebAssembly component of Firefox. This vulnerability could potentially lead to security issues due to improper handling of integer operations within WebAssembly execution. Mozilla fixed this vulnerability in Firefox 153 and Firefox ESR 140.13 as part of a security update addressing multiple high-impact bugs. The advisory does not detail exploitation methods or specific impacts beyond the high severity classification.

Potential Impact

The integer overflow in the WebAssembly component could allow an attacker to cause unexpected behavior in Firefox, potentially leading to memory corruption or other security issues. The Mozilla advisory classifies the impact as high, indicating significant risk if exploited. However, no active exploitation in the wild has been reported at this time.

Mitigation Recommendations

This vulnerability is fixed in Firefox 153 and Firefox ESR 140.13. Users and administrators should update to these versions or later to remediate the issue. Since this is a client-side application vulnerability, applying the official Mozilla updates is the recommended and effective mitigation.

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Technical Details

Gcve Source
db.gcve.eu
Osv Id
GHSA-54w4-5mrc-hfp8
Osv Schema Version
1.4.0
Aliases
["CVE-2026-16369"]
Ecosystems
[]
Database Specific Severity
null
Cvss Version
null

Threat ID: 6a5fd1591010f89cc21c9d31

Added to database: 07/21/2026, 20:06:49 UTC

Last enriched: 07/22/2026, 17:39:51 UTC

Last updated: 08/26/2026, 10:52:07 UTC

Views: 56

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