CVE-2026-44556
Analyzed
Analyzed - Analysis Complete
BaseFortify
Publication date: 2026-05-15
Last updated on: 2026-05-19
Assigner: GitHub, Inc.
Description
Description
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the /responses endpoint in the OpenAI router accepts any authenticated user and forwards requests directly to upstream LLM providers without enforcing per-model access control. While the primary chat completion endpoint (generate_chat_completion) checks model ownership, group membership, and AccessGrants before allowing a request, the /responses proxy only validates that the user has a valid session via get_verified_user. This allows any authenticated user to interact with any model configured on the instance by sending a POST request to /api/openai/responses with an arbitrary model ID. This vulnerability is fixed in 0.9.0.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| openwebui | open_webui | to 0.9.0 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-284 | The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. |
| CWE-862 | The product does not perform an authorization check when an actor attempts to access a resource or perform an action. |