---
id: CVE-2026-100779
title: Use-after-free in the XSLT component
summary: >-
  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.
severity: none
vendor: Mozilla
product: Firefox
affected:
  - Firefox
published: '2026-09-29'
updated: '2026-09-29'
sourceUpdated: '2026-09-29T13:17:42.690'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100779'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=2068417'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-100/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-97/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-98/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-99/'
    label: security@mozilla.org
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-29T13:34:31.661Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.