CVE-2026-45369: Universal-Tool-Calling-Protocol Python-Utcp

High severity, CVSS 8.3. EPSS: 0.4% chance of exploitation in the next 30 days.

python-utcp is the python implementation of UTCP. Prior to 1.1.3, the _substitute_utcp_args method in cli_communication_protocol.py inserts user-controlled tool_args values directly into shell command strings without any sanitization or escaping. These commands are then executed via /bin/bash -c (Unix) or powershell.exe -Command (Windows), allowing an attacker to inject arbitrary shell commands. This vulnerability is fixed in 1.1.3.

Affected products

• Universal-Tool-Calling-Protocol Python-Utcp: before 1.1.2 (fixed in 1.1.2)

Published 2026-05-14. Last modified 2026-06-17.