Information Exposure Affecting org.webjars.npm:webpack-dev-server package, versions [5.1.0,5.2.7)[6.0.0,6.1.0)


Severity

Recommended
0.0
medium
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.31% (23rd percentile)

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  • Snyk IDSNYK-JAVA-ORGWEBJARSNPM-21430997
  • published24 Oct 2026
  • disclosed22 Oct 2026
  • creditDaniel Coles, manus-use

Introduced: 22 Oct 2026

NewCVE-2026-114348  (opens in a new tab)
CWE-209  (opens in a new tab)

How to fix?

Upgrade org.webjars.npm:webpack-dev-server to version 5.2.7, 6.1.0 or higher.

Overview

org.webjars.npm: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 Information Exposure via the isValidHost method in lib/Server.js, where Host and :authority headers are not properly validated against malformed or URL-encoded values. An attacker can send a request with a malformed Host header that bypasses the allowedHosts check, allowing unauthorized access to the webpack-dev-server. Additionally, the editor URL handler constructs a URL using the untrusted Host header as the base, which can be exploited to cause unexpected behavior through a malformed request.

CVSS Base Scores

version 4.0
version 3.1