Improper Input Validation Affecting Firefox-ESR package, versions [,153.6)
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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- published27 Oct 2026
- disclosed27 Oct 2026
- creditUnknown
Introduced: 27 Oct 2026
NewCVE-2026-117861 (opens in a new tab)How to fix?
Upgrade Firefox-ESR to version 153.6 or higher.
Overview
Affected versions of this package are vulnerable to Improper Input Validation via the Navigation component in the DOM. An attacker can execute code outside of the intended sandboxed environment by leveraging crafted web content.