CVE-2026-45398
Description
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, _validate_collection_access() checks the user-memory-* and file-* collection name prefixes but does not check knowledge base collections, which use raw UUIDs as collection names. Any authenticated user who knows a private knowledge base UUID can read its content through the retrieval query endpoints, even though the knowledge API correctly denies that user access. The same gap affects the retrieval write endpoints (/process/text, /process/file, /process/files/batch, /process/web, /process/youtube), allowing an attacker to inject content into or overwrite another user's knowledge base. This vulnerability is fixed in 0.9.5.
How to fix
- openwebui open_webui0.9.5 or later
- open-webui0.9.5 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| openwebui open_webui | v < 0.9.5 | 0.9.5 |
| open-webuiPyPI | v < 0.9.5 | 0.9.5 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.