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CVE-2026-100772: Vulnerability in Mozilla Firefox

0
High
VulnerabilityCVE-2026-100772cvecve-2026-100772
Published: 09/29/2026 (09/29/2026, 12:36:02 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.

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

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/29/2026, 13:33:14 UTC

Technical Analysis

This vulnerability involves a use-after-free condition in the DOM: Core & HTML 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, which can lead to memory corruption and potentially exploitable conditions. Mozilla fixed this vulnerability in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. The Mozilla advisory lists this as a high impact issue and provides references to the bug tracking number 2068340.

Potential Impact

The vulnerability is classified as high impact by Mozilla, indicating that successful exploitation could lead to significant security consequences such as memory corruption. However, no known exploits in the wild have been reported at this time.

Mitigation Recommendations

An official fix is available and has been released in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. Users and administrators should update to these versions or later to remediate this vulnerability. No additional mitigation actions are indicated by the vendor advisory.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-09-26T19:15:28.393Z
State
PUBLISHED
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-100/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-99/","vendor":"Mozilla"}]

Threat ID: 6abbb3edf7a7c54106640970

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

Last enriched: 09/29/2026, 13:33:14 UTC

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

Views: 3

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