What is CVE-2026-44552?

CVE-2026-44552 is a high-severity vulnerability in Open-Webui, classified under Exposure of Resource to Wrong Sphere. CVSS score: 8.7/10. Published 2026-05-15.

How severe is CVE-2026-44552?

High severity. CVSS v3 base score is 8.7 out of 10.

Vulnerability in Open-Webui

CVE-2026-44552

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the tool_servers and terminal_servers keys in utils/tools.py do use a prefix. When two or more Open WebUI instances share a Redis database (a supported and documented deployment pattern, e.g., for multi-region deployments, blue-green setups, or cluster topologies), the unprefixed keys collide. An admin on Instance A writing to tool_servers overwrites the value read by Instance B — causing Instance B's users to receive Instance A's tool server configuration. This vulnerability is fixed in 0.9.0.

EPSS: 0.003 (22.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N.

Affected products

Open-webui — versions < 0.9.0
Openwebui Open_webui

Weakness classification (CWE)

CWE-668 — Exposure of Resource to Wrong Sphere

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)

Frequently asked questions

What is CVE-2026-44552?: CVE-2026-44552 is a high-severity vulnerability in Open-Webui, classified under Exposure of Resource to Wrong Sphere. CVSS score: 8.7/10. Published 2026-05-15.
How severe is CVE-2026-44552?: High severity. CVSS v3 base score is 8.7 out of 10.