9Router is an AI router & token saver. Prior to 0.5.2, 9Router allows a remote authenticated attacker to achieve arbitrary code execution on the host operating system by combining a Host header bypass of localhost-only routes with unvalidated MCP plugin args passed to child_process.spawn(), allowing malicious custom plugins to execute commands through /api/mcp//sse. This issue is fixed in version 0.5.2.
{
"cwe_ids": [
"CWE-78"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/62xxx/CVE-2026-62312.json",
"cna_assigner": "GitHub_M"
}