Microsoft UFO is an open-source framework for intelligent automation across devices and platforms. Prior to 3.0.9, the /api/task_result/{task_name} endpoint calls SessionManager.get_result_by_task() in ufo/server/services/session_manager.py, which acquires a non-reentrant lock and then calls SessionManager.get_result() to acquire the same lock again when the task name maps to a session. An authenticated caller who knows or creates a mapped task name can therefore block the request indefinitely, and in the default single-process server configuration the blocked event-loop thread prevents other HTTP, WebSocket, and dependent background interactions.
Unknown task names do not reach the nested call and are not affected. This issue is fixed in version 3.0.9.
Attack Parameters
Impact Assessment
CVSS Vector v3.1