Improper Input Validation Affecting webpack-dev-server package, versions <5.2.6
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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- published4 Jul 2026
- disclosed3 Jul 2026
- creditStr1ckl4nd, Zyy0530
Introduced: 3 Jul 2026
NewCVE-2026-14631 (opens in a new tab)How to fix?
Upgrade webpack-dev-server to version 5.2.6 or higher.
Overview
webpack-dev-server is an Uses webpack with a development server that provides live reloading. It should be used for development only.
Affected versions of this package are vulnerable to Improper Input Validation through the host-validation process. An attacker can cause the server to terminate unexpectedly by sending a malformed Host or Origin header in an HTTP request or WebSocket upgrade.