Access Control Bypass Affecting Firefox package, versions [,153.0)
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.
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- published25 Jul 2026
- disclosed21 Jul 2026
- creditUnknown
Introduced: 21 Jul 2026
CVE-2026-16388 (opens in a new tab)How to fix?
Upgrade Firefox to version 153.0 or higher.
Overview
Affected versions of this package are vulnerable to Access Control Bypass through the Networking component in the DOM. An attacker can execute code outside of the intended sandbox by exploiting insufficient isolation between the sandboxed environment and privileged browser processes.