CVE-2025-27426 Affecting firefox-esr package, versions <136-r0
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-CHAINGUARDLATEST-FIREFOXESR-17765121
- published1 Jul 2026
- disclosed4 Mar 2025
Introduced: 4 Mar 2025
CVE-2025-27426 (opens in a new tab)How to fix?
Upgrade Chainguard firefox-esr to version 136-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.
Malicious websites utilizing a server-side redirect to an internal error page could result in a spoofed website URL. This vulnerability was fixed in Firefox for iOS 136.