CVE-2026-46416

Microsoft UFO shared WebSocket handler state causes cross-client response hijacking

Published May 27, 2026 CVSS 3.1 · 6.3 Medium EPSS < 1% KEV · Not listed
Description
Microsoft UFO open-source framework for intelligent automation across devices and platforms. In 3.0.1-4-ge2626659, Microsoft UFO creates one shared UFOWebSocketHandler instance and reuses it for multiple authenticated WebSocket connections. The handler stores per-connection protocol objects in mutable instance fields. Each new WebSocket connection overwrites those fields. Later, message handlers send responses through the shared fields instead of through protocol objects bound to the originating connection. As a result, the most recently connected authenticated client can receive protocol responses that belong to another authenticated client.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Microsoft
Microsoft ufo
Vendors & Products Microsoft
Microsoft ufo
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Microsoft UFO open-source framework for intelligent automation across devices and platforms. In 3.0.1-4-ge2626659, Microsoft UFO creates one shared UFOWebSocketHandler instance and reuses it for multiple authenticated WebSocket connections. The handler stores per-connection protocol objects in mutable instance fields. Each new WebSocket connection overwrites those fields. Later, message handlers send responses through the shared fields instead of through protocol objects bound to the originating connection. As a result, the most recently connected authenticated client can receive protocol responses that belong to another authenticated client.
Title Microsoft UFO shared WebSocket handler state causes cross-client response hijacking
Weaknesses CWE-284
CWE-488
References
Metrics cvssV3_1

{'score': 6.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
May 28, 2026, 1:01 PM
Reserved
May 13, 2026, 9:04 PM
Status
Deferred
Published
May 27, 2026, 11:16 PM
Modified
Oct 26, 2026, 12:10 PM