Paper/Archive/CVE-2026-46339

CVE-2026-46339

decolua 9router — 9Router: Unauthenticated Remote Code Execution via unprotected MCP custom plugin routes

CVSS 10.0 (CNA)10.0 / 10 × 3030.0 Not in CISA KEV+300.0 EPSS percentile 86.3.863 × 2017.3 Exploit: SSVC poc+1010.0 SSVC exploitation: poc+100.0

Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource

9router>= 0.4.30, < 0.4.37–CNA

Scores by source

GitHub_M (CNA)10.0CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

CISA ADPSSVCExploitation: poc · Automatable: yes · Technical impact: total

References

exploitgithub.com/decolua/9router/security/advisories/GHSA-fhh6-4qxv-rpqj refgithub.com/decolua/9router/commit/992f4db4a0d858bcc86b4786f2abab117a6ccdf8