An endpoint in the Open WebUI back end allows deletion of a knowledge base; when that base references an administrator‑owned external connection, the deletion removes that connection without an administrator check or a check for other dependent knowledge bases. A user with write access to a shared external knowledge base—who is not an administrator—can therefore delete that base. The removal of the shared connection instantly disables every other knowledge base that relies on the same external connection, leading to a loss of service for all users of those bases and effectively giving the non‑administrator a privilege‑escalation effect. The weakness is captured by CWE‑269 for improper privilege management and CWE‑863 for missing authorization checks on shared resources.

The vulnerability exists in the open‑webui project and applies to all released versions from 0.10.0 up through 0.11.0, inclusive. Version 0.11.1 and later contain the fix. Therefore, any deployment of Open WebUI with a version in the affected range is susceptible.

The CVSS base score of 7.1 indicates moderate‑to‑high severity. Exploitability data (EPSS) is not available and the vulnerability is not listed in the CISA KEV catalog. The likely attack vector is via the REST API, requiring an authenticated session with write privileges to a shared knowledge base. An attacker who can invoke the /api/v1/knowledge/{id}/delete endpoint will trigger the removal of the shared external connection, causing a denial of service for all affected knowledge bases. The risk is significant for environments that allow non‑admin users write access to shared resources, as it permits widespread disruption with modest privileges.