Vulnerability Description
PraisonAI is a multi-agent teams system. Prior to version 4.6.40, PraisonAI's first-party A2A server example exposes an unauthenticated A2A JSON-RPC endpoint and registers a `calculate(expression)` tool implemented with Python `eval()`. The example also binds to `0.0.0.0`. A remote unauthenticated attacker can send `message/send` to `/a2a`; the request reaches `agent.chat()`, and a real LLM can invoke the registered `calculate` tool. In testing with `gemini/gemini-2.5-flash-lite`, this resulted in arbitrary Python execution in the server process, confirmed by creation of a marker file from an unauthenticated HTTP request. The issue affects deployments following the official A2A example or similar unauthenticated public A2A deployments with unsafe tools. The default unauthenticated A2A surface also exposes task history and task cancellation APIs, increasing confidentiality and integrity impact. Version 4.6.40 patches the issue.
CVSS Score
CRITICAL
Related Weaknesses (CWE)
References
- https://github.com/MervinPraison/PraisonAI/commit/e0fb8e7dd1ee6759c18ed07f436c21
- https://github.com/MervinPraison/PraisonAI/pull/1793
- https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-vg22-4gmj-pr
- https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-vg22-4gmj-pr
FAQ
What is CVE-2026-47391?
CVE-2026-47391 is a vulnerability with a CVSS score of 9.8 (CRITICAL). PraisonAI is a multi-agent teams system. Prior to version 4.6.40, PraisonAI's first-party A2A server example exposes an unauthenticated A2A JSON-RPC endpoint and registers a `calculate(expression)` to...
How severe is CVE-2026-47391?
CVE-2026-47391 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-47391?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.