CVE-2026-45399

Name: CVE-2026-45399
Creator: NVD / NIST
Published: 2026-05-15T20:16:48.95+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.1/10EPSS 0.27%

Last modified Jun 17, 2026

CVE-2026-45399 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, any authenticated user with low privileges can enumerate active background tasks across the system and stop tasks belonging to other users via the GET /api/tasks and POST /api/tasks/stop/{task_id} methods. EPSS estimates a 0.27% 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 0.9.0, any authenticated user with low privileges can enumerate active background tasks across the system and stop tasks belonging to other users via the GET /api/tasks and POST /api/tasks/stop/{task_id} methods. This allows a casual user to disrupt system-wide chat usage by continuously canceling other users' active tasks. This is a real authorization vulnerability affecting integrity and usability in multi-user deployments. This vulnerability is fixed in 0.9.0.

Metrics

CVSS 3.1

7.1/10

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

EPSS Probability

0.27%

18.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-862

Affected Software

Vendor	Product	Versions
Openwebui	Open Webui	< 0.9.0

References

https://github.com/open-webui/open-webui/security/advisories/GHSA-8jjp-r2w2-4v22Exploit, Mitigation, Vendor Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-8jjp-r2w2-4v22Exploit, Mitigation, Vendor Advisory

Timeline

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

Frequently Asked Questions

What is CVE-2026-45399?

How severe is CVE-2026-45399?

CVE-2026-45399 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.27% probability of exploitation in the next 30 days.

How do I fix CVE-2026-45399?

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-2026-45399?

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

Scan your code now

Source: NVD / NIST