CVE-2026-44550: open-webui Missing Authorization

Vulnerability summary

CVE-2026-44550 is a medium (CVSS 5.0) Missing Authorization vulnerability in open-webui. EPSS estimates a 0.29% chance of exploitation in the next 30 days, higher than 19.9% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 15-05-2026
   PublishedVulnerability first disclosed.
2. 15-05-2026
   Last modifiedVulnerability information updated.

Description

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, FolderForm uses model_config = ConfigDict(extra='allow'), which permits arbitrary fields to pass through Pydantic validation and be included in model_dump(exclude_unset=True). In insert_new_folder, the server-assigned user_id is placed at the start of the dict and then overwritten by the spread of form data. Because FolderModel declares user_id: str as a real field (not just a form extra), any attacker-supplied user_id in the POST body is accepted by the model and persisted on the Folder row. This vulnerability is fixed in 0.9.0.

• CWE-862Missing AuthorizationThe product does not perform an authorization check when an actor attempts to access a resource or perform an action.