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… (CVE-2026-109287)

The vulnerability in Open WebUI (CVE-2026-109287) is an authorization flaw affecting versions from 0.9.6 before 0.11.4. The knowledge base file listing endpoint does not verify that the supplied directory_id parameter belongs to the requested knowledge base. This allows users with read access to one knowledge base to access metadata about directories in other knowledge bases by supplying a retained foreign directory UUID. The exposed data includes folder names, owner user IDs, and knowledge base IDs of the directory and its ancestors, potentially leaking sensitive organizational information.

The impact is limited to information disclosure of metadata related to folder structures, owner user IDs, and knowledge base IDs. There is no indication of confidentiality breach of actual file contents, nor integrity or availability impacts. The CVSS score of 4.3 (medium severity) reflects this limited confidentiality impact with no integrity or availability impact.

No explicit patch or remediation information is provided. Since the affected versions are prior to 0.11.4, upgrading to version 0.11.4 or later is implied as a remediation step. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.