Advisories for Pypi/Utcp-Http package

HttpCommunicationProtocol.call_tool validates only the pre-redirect tool URL, then issues the request with redirects enabled and never re-checks where it lands. A tool whose endpoint is an attacker-controlled public URL can therefore 302-redirect the UTCP client into an internal service including the cloud metadata endpoint and the response body is returned to the tool caller. This is a working SSRF + internal-data-exfiltration primitive. This is the redirect invariant of the SSRF …

The utcp-http library (<= 1.1.3) unconditionally trusts the tokenUrl field embedded in remote OpenAPI security schemes. When a victim registers an attacker-controlled OpenAPI spec and invokes any generated OAuth2-protected tool, the library POSTs the victim's client_id and client_secret to the attacker-supplied token endpoint without any URL validation. The same ensure_secure_url() guard applied to discovery URLs and tool invocation URLs is absent for the OAuth2 token endpoint, creating a credential-exfiltration path.

The utcp-http plugin is vulnerable to a blind Server-Side Request Forgery (SSRF) caused by a trust-boundary inconsistency between manual discovery and tool invocation. register_manual() validates the discovery URL against an HTTPS / loopback allowlist, but call_tool() and call_tool_streaming() reuse the resolved tool_call_template.url directly without revalidating. An attacker who hosts a malicious OpenAPI spec on a legitimate HTTPS endpoint can declare servers: [{ url: "http://169.254.169.254" }] (or any internal address) in …