Mozilla Firefox Use-After-Free Vulnerability

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• cpe mozilla/firefoxversion unspecified
• cpe mozilla/firefox focusversion unspecified
• cpe mozilla/firefox mobileversion unspecified
• cpe mozilla/thunderbirdversion unspecified
• vendor Mozilla Firefoxversion unspecified

How to fix CVE-2022-26485

• Recommended remediation

  Apply updates per vendor instructions. CISA due date Mar 21, 2022.

• Official advisories

  • CISA KEV · cisa.gov
  • CVE.org · cve.org
  • FIRST EPSS · first.org
  • NIST NVD · nvd.nist.gov
  • VulnCheck KEV · vulncheck.com

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

1. Mar 7, 2022 · Catalog

   Detected

   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.

2. Mar 7, 2022 · CISA KEV

   Known exploited

   Apply updates per vendor instructions.

3. Mar 21, 2022 · CISA KEV

   Remediation due

   Apply updates per vendor instructions.

4. Aug 19, 2026 · Catalog

   Updated

   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.

Sources

• CISA KEVConfirmed exploitationCVE-2022-26485

  Mozilla Firefox contains a use-after-free vulnerability in XSLT parameter processing which can be exploited to perform arbitrary code execution.

  cisa.gov
• CVE.orgVulnerability recordCVE-2022-26485

  Official CVE identifier

  cve.org
• FIRST EPSSExploitation probabilityCVE-2022-26485

  30-day exploitation probability 14.3%

  first.org
• NIST NVDVulnerability recordCVE-2022-26485

  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

  nvd.nist.gov
• VulnCheck KEVConfirmed exploitationCVE-2022-26485

  Mozilla Firefox contains a use-after-free vulnerability in XSLT parameter processing which can be exploited to perform arbitrary code execution.

  vulncheck.com

References

• VulnCheck exploitation evidence · blog.google
• Exploit · bugzilla.mozilla.org
• VulnCheck exploitation evidence · docs.google.com
• CISA note · nvd.nist.gov
• VulnCheck exploitation evidence · raw.githubusercontent.com
• VulnCheck exploitation evidence · storage.googleapis.com
• US Government Resource · cisa.gov
• VulnCheck exploitation evidence · cisa.gov
• VulnCheck exploitation evidence · mandiant.com
• Vendor Advisory · mozilla.org

Freshness

Last verified in this catalog Oct 17, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.