---
id: CVE-2022-26485
title: >-
  Removing an XSLT parameter during processing could have lead to an exploitable
  use-after-free
summary: >-
  Removing an XSLT parameter during processing could have lead to an exploitable
  use-after-free. We have had reports of attacks in the wild abusing this flaw.
  This vulnerability affects Firefox < 97.0.2, Firefox ESR < 91.6.1, Firefox for
  A…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-416
  - CWE-416
vendor: mozilla
product: firefox
affected:
  - firefox < 91.6.1
  - firefox < 97.0.2
  - firefox_focus < 97.3.0
  - firefox_mobile < 97.3.0
  - thunderbird < 91.6.2
patched:
  - firefox 97.0.2
  - firefox_focus 97.3.0
  - firefox_mobile 97.3.0
  - thunderbird 91.6.2
published: '2022-12-22'
updated: '2026-08-19'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2022-26485'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=1758062'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2022-09/'
    label: security@mozilla.org
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=1758062'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.mozilla.org/security/advisories/mfsa2022-09/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2022-26485
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - kev
  - in-the-wild
  - exploit-available
epss: 0.14261
epssPercentile: 0.96487
kev: true
kevDateAdded: '2022-03-07'
kevDueDate: '2022-03-21'
kevRansomware: false
exploited: true
zeroDay: true
ingestedAt: '2026-08-19T15:41:15.226Z'
exploits:
  github: 1
  githubRepos:
    - 'https://github.com/mistymntncop/CVE-2022-26485'
  checkedAt: '2026-09-21T15:25:17.891Z'
exploitAvailable: true
---

## Overview

Removing an XSLT parameter during processing could have lead to an exploitable use-after-free. We have had reports of attacks in the wild abusing this flaw. This vulnerability affects Firefox < 97.0.2, Firefox ESR < 91.6.1, Firefox for Android < 97.3.0, Thunderbird < 91.6.2, and Focus < 97.3.0.

## Affected

- `firefox < 91.6.1`
- `firefox < 97.0.2`
- `firefox_focus < 97.3.0`
- `firefox_mobile < 97.3.0`
- `thunderbird < 91.6.2`

## Remediation

Upgrade past the affected range:

- `firefox 97.0.2`
- `firefox_focus 97.3.0`
- `firefox_mobile 97.3.0`
- `thunderbird 91.6.2`