CVE-2026-7321 Affecting firefox-esr package, versions <140.10.1-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.26% (17th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-CHAINGUARDLATEST-FIREFOXESR-17764263
  • published1 Jul 2026
  • disclosed28 Apr 2026

Introduced: 28 Apr 2026

CVE-2026-7321  (opens in a new tab)

How to fix?

Upgrade Chainguard firefox-esr to version 140.10.1-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream firefox-esr package and not the firefox-esr package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

Sandbox escape due to incorrect boundary conditions in the WebRTC: Networking component. This vulnerability was fixed in Firefox 150, Thunderbird 150, Firefox ESR 140.10.1, and Thunderbird 140.10.1.

CVSS Base Scores

version 3.1