# CVE-2022-26485: Mozilla Firefox Use-After-Free Vulnerability

Source: https://junglewise.ai/threats/cve-2022-26485-mozilla-firefox-use-after-free-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-03-07. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2022-26485 · Severity: critical · CVSS 8.8 · Exploited in the wild · Published 2022-03-07

Mozilla Firefox and related products contain a use-after-free vulnerability in XSLT parameter processing. Removing an XSLT parameter during processing can lead to memory corruption, which may be exploited to achieve arbitrary code execution.

Technologies: [Mozilla Firefox](https://junglewise.ai/threats/technologies/firefox), [Mozilla Firefox ESR](https://junglewise.ai/threats/technologies/firefox-esr), [Mozilla Thunderbird](https://junglewise.ai/threats/technologies/thunderbird). Vendors: [Mozilla](https://junglewise.ai/threats/vendors/mozilla).

## Quick answers

**Is CVE-2022-26485 exploited in the wild?** Yes. CVE-2022-26485 is known to be exploited in the wild, first recorded on 7 March 2022. Treat it as urgent.

**How severe is CVE-2022-26485?** Critical severity, with a CVSS score of 8.8, published 7 March 2022.

**Which products and versions are affected?** Mozilla Firefox < 97.0.2; Mozilla Firefox ESR < 91.6.1; Mozilla Firefox for Android < 97.3.0; Mozilla Thunderbird < 91.6.2; and 1 more.

**Is there a fix for CVE-2022-26485?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2022-26485 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2022-26485?** Check whether you run Mozilla Firefox, Mozilla Firefox ESR or Mozilla Thunderbird. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Mozilla Firefox < 97.0.2
- Mozilla Firefox ESR < 91.6.1
- Mozilla Firefox for Android < 97.3.0
- Mozilla Thunderbird < 91.6.2
- Mozilla Focus < 97.3.0

## Timeline

- 2022-03-07: disclosed: Vulnerability published and added to CISA KEV catalog.
- 2022-03-07: kev added
- 2022-03-07: exploited: Reports of attacks in the wild abusing this flaw.

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