CVE-2026-45396

Name: CVE-2026-45396
Creator: NVD / NIST
Published: 2026-05-15T21:16:37.59+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.4/10EPSS 0.31%

Last modified Jun 17, 2026

CVE-2026-45396 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. 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'). EPSS estimates a 0.31% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

5.4/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

EPSS Probability

0.31%

22.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-915

Affected Software

Vendor	Product	Versions
Openwebui	Open Webui	< 0.9.5

References

https://github.com/open-webui/open-webui/security/advisories/GHSA-rjmp-vjf2-qf4gExploit, Vendor Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-rjmp-vjf2-qf4gExploit, Vendor Advisory

Timeline

Published: May 15, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-45396?

How severe is CVE-2026-45396?

CVE-2026-45396 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 0.31% probability of exploitation in the next 30 days.

How do I fix CVE-2026-45396?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-45396?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST