CVE-2026-34935
CRITICALCVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
4Tags
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.
Analysis
Arbitrary OS command execution in PraisonAI (Python package) versions prior to 4.5.69 allows remote unauthenticated attackers to execute commands as the process user via the unsanitized `--mcp` CLI argument. The vulnerability stems from passing user-controlled input directly to `shlex.split()` and `anyio.open_process()` without validation. …
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Remediation
Within 24 hours: Identify all systems running PraisonAI and determine currently installed versions using `pip show praisonai`. Within 7 days: Upgrade all affected instances to PraisonAI version 4.5.69 or later using `pip install --upgrade praisonai>=4.5.69` and validate the upgrade with `pip show praisonai`. …
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GHSA-9gm9-c8mq-vq7m