CVE-2026-46538CWE-294CWE-345

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

Medium · published May 27, 2026

CVSS v3.1
5.9
EPSS
0%
Percentile
21.0
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L
CVSS v4.0
Not supplied
EPSS
0.00295 · 21.0th percentile
Weaknesses
CWE-294 · Authentication Bypass by Capture-replay; CWE-345 · Insufficient Verification of Data Authenticity
Published
2026-05-27T21:56Z
EPSS history
Timeline
  • 27 MAY 21:56Z
    Microsoft UFO accepts cross-device TASK_END messages by session_id only, allowing peer task-result injection
    cvelistv5