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CVE-2026-100796: Vulnerability in Mozilla Firefox

0
High
VulnerabilityCVE-2026-100796cvecve-2026-100796
Published: 09/29/2026 (09/29/2026, 12:36:16 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 157.

CVSS v3.1

Score 8.8high

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

Affected software

Mozilla

Firefox

GitHub Actionsmore threats →ai
mozilla/firefox
pkg:github/mozilla/firefox
Affected versions
<157

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/29/2026, 13:18:17 UTC

Technical Analysis

This vulnerability involves a use-after-free condition in the JavaScript: WebAssembly component of Mozilla Firefox. Use-after-free vulnerabilities occur when a program continues to use a pointer after the memory it points to has been freed, potentially leading to memory corruption. Mozilla fixed this vulnerability in Firefox 157 as part of a large batch of memory safety fixes. The vendor advisory lists this vulnerability with moderate impact and references Bug 2049604 for technical details.

Potential Impact

The vulnerability could allow an attacker to cause memory corruption, potentially leading to crashes or other unintended behavior. Mozilla rates the impact as moderate for this specific vulnerability. There are no known exploits in the wild at the time of publication.

Mitigation Recommendations

Mozilla fixed this vulnerability in Firefox 157. Users and administrators should update to Firefox 157 or later to remediate this issue. Since this is not a cloud service, patching the client software is required. No additional mitigation steps are indicated by the vendor advisory.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-09-26T19:17:33.309Z
State
PUBLISHED
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","vendor":"Mozilla"}]

Threat ID: 6abbb3f3f7a7c5410664099c

Added to database: 09/29/2026, 12:49:55 UTC

Last enriched: 09/29/2026, 13:18:17 UTC

Last updated: 09/29/2026, 18:20:12 UTC

Views: 7

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