Low 3.1Published Sep 27, 2026

CVE-2026-101057utcp-mcp before 1.1.3 SSRF via unvalidated MCP server URL

Updated under an hour ago (2026-10-19 11:10 UTC)

Does this affect you?

It affects universal-tool-calling-protocol python-utcp. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for universal-tool-calling-protocol python-utcp

Exploited in the last 30 days

utcp-mcp (the MCP plugin of python-utcp) through 1.1.2 connects to the HTTP and WebSocket MCP server URLs given in a call template's mcpServers configuration without the ensure_secure_url validation that the HTTP-family plugins apply, so the HTTPS/WSS-or-loopback rule is not enforced. A call template naming a plain-HTTP, non-loopback MCP server URL is dialed as configured, exposing the MCP handshake to network interception and permitting cleartext connections to internal hosts. The mcpServers configuration is operator-authored rather than remote data, and the connection is an MCP handshake rather than an arbitrary request returning a body, which limits practical exploitation; the OAuth2 token_url credential path described in the original report was not reachable in the affected versions, because the OAuth2 handler was never invoked and the call template's auth field was not read. Fixed in utcp-mcp 1.1.3, which validates server URLs before any connection is made.

CVSS: 3.1 LOW (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N
Weakness (CWE): CWE-319
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Deferred
Record last updated: Sep 30, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

universal-tool-calling-protocol python-utcp universal_tool_calling_protocol:python_utcp (from the name)	before 1.1.3; 1.1.3 not affected	CNA record

References

https://github.com/universal-tool-calling-protocol/python-utcp/security/advisories/GHSA-qwr9-cj2c-v3fvvendor-advisory
https://www.vulncheck.com/advisories/utcp-mcp-before-1.1.3-ssrf-via-unvalidated-mcp-server-urlthird-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.