# CVE-2026-8094: Mozilla Firefox and Thunderbird code injection in WebRTC

Source: https://junglewise.ai/threats/cve-2026-8094-mozilla-firefox-and-thunderbird-code-injection-in-webrtc  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-07. Updated: 2026-06-30  
License: CC BY 4.0 with a link back

CVE-2026-8094 · Severity: critical · CVSS 9.8 · Published 2026-05-07

A critical security vulnerability has been identified in the WebRTC component of Mozilla Firefox and Thunderbird, which are widely used for web browsing and email communication. This flaw could allow a remote attacker to execute unauthorized code or gain control over an affected system. While Thunderbird users are generally protected when reading standard emails, the risk remains high in browser-like contexts or if malicious scripts are executed.

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-2026-8094 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-8094 being exploited in the wild.

**How severe is CVE-2026-8094?** Critical severity, with a CVSS score of 9.8, published 7 May 2026.

**Which products and versions are affected?** Mozilla Firefox ESR < 140.10.2, up to (excluding) 140.10.2; Mozilla Thunderbird < 140.10.2.

**Is there a fix for CVE-2026-8094?** A patch was published on 2026-05-07: Fixed in Firefox ESR 140.10.2 and Thunderbird 140.10.2 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-8094 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-8094?** Check whether you run Mozilla Firefox, Mozilla Firefox ESR or Mozilla Thunderbird at an affected version. 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.

## Technical details

This vulnerability is classified as a code injection issue (CWE-94) within the WebRTC component of Mozilla products. The flaw allows for improper control of code generation, which can be leveraged by a remote, unauthenticated attacker to execute arbitrary code on the target system. The attack vector is network-based and, according to CISA-ADP, does not require user interaction or elevated privileges, resulting in a CVSS score of 9.8. Mozilla has addressed this in Firefox ESR 140.10.2 and Thunderbird 140.10.2. Red Hat has also released corresponding updates for various Enterprise Linux versions.

## Affected products

- Mozilla Firefox ESR < 140.10.2
- Mozilla Thunderbird < 140.10.2
- Red Hat Enterprise Linux 8, 9, 10

## Timeline

- 2026-05-07: advisory: Mozilla Foundation Security Advisory 2026-41 published
- 2026-05-07: patched: Fixed in Firefox ESR 140.10.2 and Thunderbird 140.10.2
- 2026-05-19: advisory: Red Hat security advisory RHSA-2026:19160 published

## References

- [https://bugzilla.mozilla.org/show_bug.cgi?id=2035939](https://bugzilla.mozilla.org/show_bug.cgi?id=2035939)
- [https://www.mozilla.org/security/advisories/mfsa2026-41/](https://www.mozilla.org/security/advisories/mfsa2026-41/)
- [https://www.mozilla.org/security/advisories/mfsa2026-44/](https://www.mozilla.org/security/advisories/mfsa2026-44/)
- [https://access.redhat.com/errata/RHSA-2026:19160](https://access.redhat.com/errata/RHSA-2026:19160)
- [https://access.redhat.com/errata/RHSA-2026:20566](https://access.redhat.com/errata/RHSA-2026:20566)
- [https://access.redhat.com/errata/RHSA-2026:20574](https://access.redhat.com/errata/RHSA-2026:20574)
- [https://access.redhat.com/errata/RHSA-2026:24508](https://access.redhat.com/errata/RHSA-2026:24508)

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