MCP Inspector proxy server lacks authentication between the Inspector client and proxy
97Vexday Risk Score
Patch now. It exploitation observed by VulnCheck and has a working public exploit.
ssvc Actcvss 9.4epss 45%
from disclosure to weapon20 days
Published on NVDJun 13
1st PoC+20d
VulnCheck+124d
exploitation probability
45%top 1% of all CVEs
observed exploitation
yesVulnCheck
5 public exploit(s)
The MCP inspector is a developer tool for testing and debugging MCP servers. Versions of MCP Inspector below 0.14.1 are vulnerable to remote code execution due to lack of authentication between the Inspector client and proxy, allowing unauthenticated requests to launch MCP commands over stdio. Users should immediately upgrade to version 0.14.1 or later to address these vulnerabilities.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Affected products
modelcontextprotocol · inspectorpublic PoCs found — 5
githubgithub.com/ashiqrehan-21/MCP-Inspector-CVE-2025-49596★ 0githubgithub.com/pppxo/CVE-2025-49596-PoC★ 0githubgithub.com/acseguin21/trust-boundary-ctf★ 0vulncheckvulncheck.com/xdb/ecd7319bf73dunverifiedvulncheckvulncheck.com/xdb/eaa00f3addf7unverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
References
https://github.com/modelcontextprotocol/inspector/commit/50df0e1ec488f3983740b4d28d2a968f12eb8979https://github.com/modelcontextprotocol/inspector/security/advisories/GHSA-7f8r-222p-6f5ghttps://thenewstack.io/mcp-vulnerability-exposes-the-ai-untrusted-code-crisishttps://www.oligo.security/blog/critical-rce-vulnerability-in-anthropic-mcp-inspector-cve-2025-49596