PraisonAI Unsafe Tool Resolution Vulnerability

PraisonAI’s praisonaiagents library exhibits an unsafe tool resolution vulnerability. Specifically, when resolving tool names, the system searches module globals and the __main__ scope after failing to find a match in the declared tool list or the tool registry. Crucially, the default agent configuration sets _perm_allow to None, meaning that the permission gate does not enforce a strict allowlist of declared tools. This allows an attacker who can control or influence the tool-call names to invoke unintended application callables, bypassing the intended security boundary of declared tools. The vulnerability was verified on commit d8a8a786915dc67a7c3021e24f72458f2eac5d9c (v4.6.35).

Attack Chain

1. The attacker identifies an application callable that is accessible via __main__ or globals.
2. The attacker crafts a malicious input to the PraisonAI agent that specifies the name of the target callable as the “tool” to execute.
3. The ToolExecutionMixin.execute_tool function is called with the attacker-controlled tool name.
4. The agent first searches for the tool in its declared self.tools list. This search fails because the tool is undeclared.
5. The agent then attempts to retrieve the tool from the tool registry. This also fails.
6. The agent falls back to searching for the tool name in globals() and __main__. The attacker-specified callable is found in __main__.
7. The agent executes the callable directly, passing arguments as needed.
8. The attacker achieves arbitrary code execution within the context of the PraisonAI application, potentially leading to unauthorized state changes, data exposure, or command execution.

Impact

Successful exploitation of this vulnerability can have significant consequences. In deployments where untrusted parties can influence tool-call names, attackers can execute undeclared application callables, bypassing intended security boundaries. Operators who rely on the declared tool list as a security control are vulnerable, as this control can be circumvented. If the application keeps privileged helper functions in process scope, the attacker can reuse those helpers with the application’s own privileges, potentially leading to unauthorized state changes, data exposure, or command execution. Affected packages include pip/praisonaiagents (vulnerable: <= 1.6.36) and pip/PraisonAI (vulnerable: <= 4.6.36).

Recommendation

• Upgrade to a patched version of praisonaiagents and PraisonAI that addresses the unsafe tool resolution (CVE-2026-44339).
• Configure the PraisonAI agent to use an explicit allowlist (_perm_allow) of permitted tools to prevent the execution of undeclared callables. Refer to the PraisonAI documentation for instructions on setting up the _perm_allow parameter.
• Implement input validation and sanitization on tool-call names to prevent attackers from injecting arbitrary callable names.
• Deploy the Sigma rule to detect attempts to execute undeclared functions through ToolExecutionMixin.