CVE-2026-46538 MEDIUM

CVE-2026-46538: Microsoft UFO accepts cross-device TASK_END messages by session_id only, allowing peer task-result injection

Vendor Microsoft
Product UFO
Weakness CWE-294
Published May 27, 2026
Last update May 28, 2026

CVSS base score

5.9/10
Attack vector Network
Attack complexity High
Privileges required Low
User interaction None
Confidentiality None
Integrity High

CVSS vector

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

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's constellation client tracks pending task responses by session_id only and does not verify that a TASK_END message came from the device that originally received the task. When the constellation sends a task to a target device, it records a pending Future under a session key. The pending task record stores the expected device ID, but the completion path ignores that binding. If another authenticated peer device sends a forged TASK_END with the same session_id, the constellation accepts the response and completes the victim device's pending Future with attacker-controlled result data. This is an authenticated cross-device task-result injection issue.

Key dates

02Disclosure timeline

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