User Impersonation Affecting 9router package, versions <0.5.2


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.25% (16th percentile)

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  • Snyk IDSNYK-JS-9ROUTER-17950959
  • published11 Jul 2026
  • disclosed10 Jul 2026
  • creditUnknown

Introduced: 10 Jul 2026

NewCVE-2026-55641  (opens in a new tab)
CWE-290  (opens in a new tab)

How to fix?

Upgrade 9router to version 0.5.2 or higher.

Overview

9router is a 9Router CLI - Start and manage 9Router server

Affected versions of this package are vulnerable to User Impersonation via manipulation of the Host header. An attacker can gain unauthorized access to the /v1 proxy and trigger server-side requests to internal or cloud-metadata hosts by spoofing the Host header to bypass authentication checks.

CVSS Base Scores

version 4.0
version 3.1