---
id: "CVE-2026-129094"
page: "https://infrastack.ai/live/CVE-2026-129094"
kind: "vulnerability"
aliases: ["CVE-2026-129094"]
title: "@utcp/http: SSRF lets remote manuals reach loopback services on agent machines"
severity: "medium"
cvss: 4.7
epss: null
exploited: false
status: "open"
category: "ai-tooling"
products: []
ecosystems: []
tags: ["agents", "ai-tooling", "mcp", "node", "utcp"]
not_affected_if: ["local-tools-only", "trusted-endpoints-only"]
published_at: "2026-11-13T16:18:59+00:00"
first_seen_at: "2026-11-13T16:47:33+00:00"
updated_at: "2026-11-13T16:49:00+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-129094", "first_seen_at": "2026-11-13T16:47:33+00:00"}]
exploit_sources: []
---

# @utcp/http: SSRF lets remote manuals reach loopback services on agent machines

Link for people: https://infrastack.ai/live/CVE-2026-129094 (this .md is for agents)

The @utcp/http package before 1.1.14 fails to block loopback addresses when a {host} placeholder is used, so remote tool manuals can reach local services. An attacker can use host values like 127.0.0.1 or register tools through Streamable HTTP and SSE discovery to reach internal services on the machine running the agent.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed version of `@utcp/http` in the project's lockfile or with `npm ls @utcp/http`
- Look for agents that load tool manuals from remote URLs and use the `{host}` placeholder

## Fix

- `@utcp/http` to `1.1.14` or later

## Timeline

- 2026-11-13T16:47:33+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-129094

## Documents

- [advisory] Vendor advisory: github.com https://github.com/universal-tool-calling-protocol/typescript-utcp/security/advisories/GHSA-r8j5-8747-88cm
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/utcp-http-before-1.1.14-ssrf-to-loopback-via-host-placeholder-in-call-templates

## From the sources

@utcp/http before 1.1.14 contains a server-side request forgery vulnerability that allows remote manuals to reach loopback services by bypassing the remote-loopback check with a {host} placeholder. Attackers can supply host arguments like 127.0.0.1 or register tools via Streamable HTTP and SSE discovery to access internal services on the agent machine.

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_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_