CVE-2026-63732

9router 0.4.59 (fixed in 0.4.60) contains a chain of vulnerabilities: a hardcoded default password (123456) that authenticates any fresh installation, a bypass of the LOCAL_ONLY network gate via a spoofed Host header, and unvalidated arguments passed to child_process.spawn() when registering MCP plugins. A remote, unauthenticated attacker can log in with the default credential, spoof the Host header to reach local-only routes, and register a malicious MCP plugin (e.g. node -e <payload>) to achieve arbitrary code execution on the host operating system when the plugin's SSE endpoint is triggered.

CVSS v3 9.9 CRITICAL

9.9^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.1 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/decolua/9router/security/advisories/GHSA-4922-8r65-fq26
https://www.vulncheck.com/advisories/9router-before-remote-code-execution-via-default-password

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-23 22:16

Updated : 2026-07-28 16:07

NVD link : CVE-2026-63732

Mitre link : CVE-2026-63732

CVE.ORG link : CVE-2026-63732

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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