| Component | Open WebUI |
| Severity | high (CVSS 7.6) |
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L |
| Published (NVD) | 2026-05-15 |
| Last modified | 2026-06-17 |
| Affected versions | open_webui < 0.9.0 |
| Fixed in | 0.9.0 |
| Weakness | CWE-862 |
| 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, Open WebUI supports model composition via base_model_id: a user-defined model (e.g., "Cheap Assistant") can reference an existing base model (e.g., "gpt-4-turbo-restricted") that provides the actual inference capability. When a user queries the composed model, the access control pipeline verifies the user has access to the composed model but never re-verifies access to the chained base model. Additionally, the model creation and import endpoints accept arbitrary base_model_id values without checking that the caller has access to that base model. Combined, this allows any user with the default model creation permission to create a model that chains to a restricted base model — and then invoke it, causing the server to dispatch the request to the restricted base model using the admin-configured API key. 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...