CVE-2026-63732: 9router before 0.4.60 Remote Code Execution via default password

Severity: critical (CVSS 9.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-23 · updated 2026-10-24
Weakness: CWE-78

Description

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.

Affected products

decolua 9router: before 0.4.60 — fixed in 0.4.60

How to fix

Upgrade to a fixed version: decolua 9router 0.4.60. Check the vendor advisory for mitigations.

References

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