CVE-2025-6431 Affecting firefox-esr package, versions <140-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.21% (12th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-FIREFOXESR-17765059
  • published1 Jul 2026
  • disclosed24 Jun 2025

Introduced: 24 Jun 2025

CVE-2025-6431  (opens in a new tab)

How to fix?

Upgrade Chainguard firefox-esr to version 140-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.

When a link can be opened in an external application, Firefox for Android will, by default, prompt the user before doing so. An attacker could have bypassed this prompt, potentially exposing the user to security vulnerabilities or privacy leaks in external applications. This bug only affects Firefox for Android. Other versions of Firefox are unaffected.. This vulnerability was fixed in Firefox 140.

CVSS Base Scores

version 3.1