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CVE-2026-100790: Vulnerability in Mozilla Firefox

0
High
VulnerabilityCVE-2026-100790cvecve-2026-100790
Published: 09/29/2026 (09/29/2026, 12:36:12 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Use-after-free in the XSLT component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, 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, 13:18:37 UTC

Technical Analysis

This vulnerability involves a use-after-free condition in the XSLT component of Mozilla Firefox, which could potentially allow attackers to execute arbitrary code or cause memory corruption. Mozilla has fixed this vulnerability in multiple Firefox ESR and standard releases, specifically in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The fix is part of a broader security update addressing multiple high-impact memory safety issues.

Potential Impact

The vulnerability is classified as high impact due to the use-after-free nature, which can lead to memory corruption and potentially arbitrary code execution. However, there are no known exploits in the wild currently. The issue affects the security and stability of Firefox browsers prior to the fixed versions.

Mitigation Recommendations

Users and administrators should update Firefox to at least Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, or Firefox ESR 140.17 to mitigate this vulnerability. Mozilla has officially fixed this issue in these releases. No additional mitigation is required beyond applying these updates.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-09-26T19:17:18.478Z
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/mfsa2026-98/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-99/","vendor":"Mozilla"}]

Threat ID: 6abbb3f1f7a7c5410664098e

Added to database: 09/29/2026, 12:49:53 UTC

Last enriched: 09/29/2026, 13:18:37 UTC

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

Views: 2

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