CVE-2026-87998

Name of the Vulnerable Software and Affected Versions Open WebUI versions 0.10.0 through 0.11.0

Description An issue exists in the knowledge base delete handler where a non-administrator user with write access to an external knowledge base can delete the shared instance configuration. This occurs because the system authorizes the deletion of the knowledge base but fails to perform a separate administrator check or verify if other knowledge bases depend on the same external connection before removing it. This affects deployments using external providers such as qdrant, milvus, or pgvector.

An attacker can exploit this by sending a request to the endpoint DELETE /api/v1/knowledge/{id}/delete. By targeting a knowledge base they have write access to, they can wipe the shared connection configuration, rendering all other knowledge bases bound to that connection unavailable. This results in a denial of service for those knowledge bases, as retrieval attempts will fail with an "External knowledge connection not found" error.

Recommendations Update Open WebUI to version 0.11.1.