CVE-2026-46544 MEDIUM

CVE-2026-46544: Microsoft UFO reuses client-supplied WebSocket session IDs and replays stale task results to new authenticated requesters

Vendor Microsoft
Product UFO
Weakness CWE-639 · IDOR
Published May 27, 2026
Last update May 28, 2026

CVSS base score

5.3/10
Attack vector Network
Attack complexity High
Privileges required Low
User interaction None
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

What the vulnerability does

01Description

Microsoft UFO open-source framework for intelligent automation across devices and platforms. In 3.0.1-4-ge2626659, Microsoft UFO accepts client-supplied session_id values in WebSocket task messages and reuses an existing in-memory session object if that session_id already exists. If a prior session has completed and remains in memory with populated results, a different authenticated client can send a new TASK message using the same session_id. The server re-enters the existing session object and sends the stale stored result to the new requester through the normal send_task_end() callback path. This is an authenticated cross-client stale result replay issue. The issue requires that the attacker knows or can predict a live or recently completed session_id.

Key dates

02Disclosure timeline

May 27, 2026 CVE published
May 28, 2026 Record updated