CVE-2026-46544

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

Published May 27, 2026 CVSS 3.1 · 5.3 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 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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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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 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.
Title Microsoft UFO reuses client-supplied WebSocket session IDs and replays stale task results to new authenticated requesters
Weaknesses CWE-639
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
May 28, 2026, 1:18 PM
Reserved
May 14, 2026, 8:42 PM
Status
Deferred
Published
May 27, 2026, 11:16 PM
Modified
Oct 26, 2026, 12:10 PM