Missing Authorization in Open WebUI - #VU136841

 

Missing Authorization in Open WebUI - #VU136841

Published: July 3, 2026


Vulnerability identifier: #VU136841
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: N/A
CWE-ID: CWE-862
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: Open WebUI
Affected software:
Open WebUI

Detailed vulnerability description

The vulnerability allows a remote user to execute arbitrary code in another user's authenticated browser session and, if the victim is an administrator, execute arbitrary code on the server.

The vulnerability exists due to missing authorization in the Socket.IO event-caller get_event_call() when processing a client-supplied session_id. A remote user can send a specially crafted chat completion request with another user's session identifier to execute arbitrary code in another user's authenticated browser session and, if the victim is an administrator, execute arbitrary code on the server.

Exploitation requires user interaction and access to a shared note that exposes the victim's live socket identifier to a read-access participant.


Remediation

Install security update from vendor's website.

Sources