The A2U (Agent-to-User) event stream server in PraisonAI exposes all agent activity without authentication. This is a separate component from the gateway server fixed in CVE-2026-34952.
The create_a2u_routes() function registers the following endpoints with NO authentication checks:
An unauthenticated attacker can:
This exposes sensitive agent activity including responses, internal reasoning, and tool call arguments to any network attacker.
[1] POST /a2u/subscribe (no auth token) Status: 200 Response: {"subscription_id":"sub-a1ad8a6edd8b","stream_name":"events", "stream_url":"http://testserver/a2u/events/sub-a1ad8a6edd8b"} Got subscription_id: sub-a1ad8a6edd8b
[2] GET /a2u/info (no auth token) Status: 200 Response: {"name":"A2U Event Stream","version":"1.0.0", "streams":["events"],"event_types":["agent.started","agent.thinking", "agent.tool_call","agent.response","agent.completed","agent.error"]}
[3] GET /a2u/health (no auth token)
Status: 200
Response: {"status":"healthy","active_subscriptions":1,"active_streams":1}
Impact: Attacker can subscribe and receive ALL agent events including responses, tool calls, and internal reasoning in real-time