Use of Less Trusted Source Affecting Firefox-ESR package, versions [,140.8.0)
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.
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-UNMANAGED-FIREFOXESR-15348155
- published25 Feb 2026
- disclosed24 Feb 2026
- creditUnknown
Introduced: 24 Feb 2026
CVE-2026-2791 (opens in a new tab)How to fix?
Upgrade Firefox-ESR to version 140.8.0 or higher.
Overview
Affected versions of this package are vulnerable to Use of Less Trusted Source due to insufficient enforcement of security controls in the Networking: Cache component. An attacker can bypass intended mitigations by exploiting weaknesses in the cache handling process.