What is CVE-2026-45398?

CVE-2026-45398 is a high-severity vulnerability in Open-webui, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 7.5/10. Published 2026-05-15.

How severe is CVE-2026-45398?

High severity. CVSS v3 base score is 7.5 out of 10.

Auth bypass in Open-webui

CVE-2026-45398

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, _validate_collection_access() checks the user-memory-* and file-* collection name prefixes but does not check knowledge base…

Vulnerability class: IDOR (Insecure Direct Object Reference)

EPSS: 0.000 (13.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Open-webui — versions < 0.9.5
Openwebui Open_webui

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)
security-advisories@github.com (Patch, x_refsource_MISC, Issue Tracking)
security-advisories@github.com (x_refsource_MISC, Release Notes)

Frequently asked questions

What is CVE-2026-45398?: CVE-2026-45398 is a high-severity vulnerability in Open-webui, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 7.5/10. Published 2026-05-15.
How severe is CVE-2026-45398?: High severity. CVSS v3 base score is 7.5 out of 10.