GitHub Advisoryadvisory · PyPI

GHSA-9gm9-c8mq-vq7m PraisonAI: OS Command Injection in MCPHandler.parse_mcp_command()

CRITICAL Published 2026-04-01 Modified 2026-04-06 Official page ↗
Aliases
CVE-2026-34935
Ecosystem
PyPI
Packages
praisonai
Severity
Critical
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weaknesses
CWE-78
Reviewed
2026-04-01

Affected packages

• PyPI praisonai: >= 4.5.15, < 4.5.69 → fixed in 4.5.69

Description

Summary The `--mcp` CLI argument is passed directly to `shlex.split()` and forwarded through the call chain to `anyio.open_process()` with no validation, allowlist check, or sanitization at any hop, allowing arbitrary OS command execution as the process user. Details `cli/features/mcp.py:61` (source) -> `praisonaiagents/mcp/mcp.py:345` (hop) -> `mcp/client/stdio/__init__.py:253` (sink) ```python source parts = shlex.split(command) hop cmd, args, env = self.parse_mcp_command(command, env_vars) self.server_params = StdioServerParameters(command=cmd, args=arguments) sink process = await anyio.open_process([command, *args]) ``` Fixed in commit `47bff65413beaa3c21bf633c1fae4e684348368c` (v4.5.69) by introducing a command allowlist: ```python ALLOWED_COMMANDS = {"npx", "uvx", "node", "python"} if cmd not in ALLOWED_COMMANDS: raise ValueError(f"Disallowed command: {cmd}") ``` PoC ```python tested on: praisonai==4.5.48 install: pip install praisonai==4.5.48 run: praisonai --mcp "bash -c 'id > /tmp/pwned'" verify: cat /tmp/pwned expected output: uid=1000(...) gid=1000(...) groups=1000(...) ``` Impact Any deployment where the `--mcp` argument is influenced by untrusted input is exposed to full OS command execution as the process user. No authentication is required.

Related

Alias · CVE (1)

  • CVE-2026-34935 PraisonAI is a multi-agent teams system. vulnerability

Weakness · CWE (1)

  • CWE-78 Improper Neutralization of Special Elements used in an OS Command weakness

References