Incorrect authorization in Open WebUI - #VU146344
Published: August 31, 2026
Vulnerability details
The vulnerability allows a remote user to delete administrator-owned external knowledge connections and cause a denial of service.
The vulnerability exists due to incorrect authorization in the knowledge base delete handler in backend/open_webui/routers/knowledge.py when handling DELETE /api/v1/knowledge/{id}/delete requests for external knowledge bases. A remote user can delete a knowledge base with write access to remove a shared external connection from instance configuration and cause a denial of service.
Only deployments using external knowledge bases backed by qdrant, milvus, or pgvector are affected. Read access alone is insufficient, and the issue is more severe when multiple knowledge bases share the same connection.