| Component | Open WebUI |
| Severity | high (CVSS 8.7) |
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N |
| Published (NVD) | 2026-05-15 |
| Last modified | 2026-06-17 |
| Affected versions | open_webui < 0.9.0 |
| Fixed in | 0.9.0 |
| Weakness | CWE-668 |
| CISA KEV | not listed |
NVD description
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.
What to do
- Upgrade Open WebUI to
0.9.0or later. - Do not expose the component's API or UI to the internet without authentication in front of it.
Sources
Read more
Other Open WebUI CVEs
Open WebUI before 0.11.4 contains a stored cross-site scripting vulnerability in MarkdownInlineTokens.svelte, which renders markdown link UR...
Open WebUI from 0.11.0 before 0.11.4 contains an improper authorization vulnerability in the chat fork handler, which places forked chats in...
Open WebUI from 0.11.1 before 0.11.4 contains an authorization bypass in the OAuth token exchange endpoint, which reads role claims only fro...
Open WebUI from 0.7.0 before 0.11.4 contains a cross-origin message handling vulnerability in SyncStatsModal that allows any website to stea...
Open WebUI from 0.6.0 before 0.11.4 contains an improper access control vulnerability in has_access_to_file that lets former knowledge base...
Open WebUI from 0.9.6 before 0.11.4 contains an authorization flaw where the knowledge base file listing does not verify that a supplied dir...