Vulnerability Analysis
9Router: Unauthenticated Remote Code Execution via unprotected MCP custom plugin routes
CVE-2026-46339
9Router is an AI router & token saver. From 0.4.30 until 0.4.37, 9Router's src/proxy.js middleware did not protect /api/cli-tools/* and /api/mcp/*, allowing unauthenticated registration of customPlugins through src/app/api/cli-tools/cowork-settings/route.js and command execution through the MCP bridge. This vulnerability is fixed in 0.4.37.
Nuclei Template
Injection
CVSS Base Score
10.0
CRITICAL
Exploitability:3.9
Impact Score:6.1
Temporal Score:-
EPSS:4.57%
Threat Intelligence Signals
CISA KEV
No
KEV Date Added
—
Ransomware Use
—
KEV Due Date
—
VulnCheck In-the-Wild
No
Nuclei Template
YES
EPSS Score
4.572%
EPSS Percentile
90.6th pct
GHSA ID
GitHub Severity
CRITICAL
SSVC Exploitation
Proof of Concept
SSVC Automatable
Yes
Vulnerability Class
Injection
Identity & Timeline
| Status | - |
| Assigning Authority | - |
| CVSS Version / Source | - |
| Reserved | - |
| Published | - |
| Patch Date (date_public) | - |
| Exploit DB Date | - |
| First GitHub PoC Date | - |
| Last Updated | - |
| Time to Patch (Days to fix) | - |
| Exploit Release Gap | - |
| PoC Release Gap | - |
| Exploit DB References | None identified |
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| No affected products specified. | ||
Social Buzz