CVE-2026-45396

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, the POST /api/v1/evaluations/feedback endpoint in Open WebUI v0.9.2 is vulnerable to mass assignment via FeedbackForm, which uses model_config = ConfigDict(extra='allow'). Due to an insecure dictionary merge order in insert_new_feedback(), an authenticated attacker can inject a user_id field in the request body that overwrites the server-derived value, creating feedback records attributed to any arbitrary user. This corrupts the model evaluation leaderboard (Elo ratings) and enables identity spoofing. This vulnerability is fixed in 0.9.5.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/open-webui/open-webui/security/advisories/GHSA-rjmp-vjf2-qf4g	Exploit Vendor Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-rjmp-vjf2-qf4g	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-15 21:16

Updated : 2026-06-17 10:52

NVD link : CVE-2026-45396

Mitre link : CVE-2026-45396

CVE.ORG link : CVE-2026-45396

JSON object : View

Products Affected

openwebui

open_webui

CWE

CWE-915

Improperly Controlled Modification of Dynamically-Determined Object Attributes

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