CVE-2026-45396

What it is

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.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. Limited direct impact.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-05-15 21:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 10:52 UTC Last updatedMost recent change to the record

Details

Published

2026-05-15 21:16 UTC

Last modified

2026-06-17 10:52 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-915

Record status

Analyzed

Affected

• Openwebui Open Webui < 0.9.5

Attack profile CVSS 3.1 · 5.4

Attack vector

Network

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

Low