CVE-2026-55546

Name of the Vulnerable Software and Affected Versions QWED-MCP versions prior to 0.2.1

Description The verify math expression() function in src/qwed mcp/engines/math engine.py passes the expression and claimed result strings directly to SymPy's parse expr() function. The implementation only normalizes caret syntax to Python exponent syntax without restricting the global dict, removing Python built-ins, or validating the expression's Abstract Syntax Tree (AST). Since parse expr() internally calls Python's eval() with built-ins available, an attacker can use Python import functionality to execute arbitrary operating-system commands as the process user, read or modify accessible data, exfiltrate secrets, or reach internal services. While the default MCP tool registry does not expose this function, exploitation is possible through downstream integrations that invoke the library API with untrusted input.

Recommendations Update to version 0.2.1. As a temporary workaround, restrict access to the verify math expression() function to prevent untrusted input from reaching the API.