Cross-User File Access via Unchecked file_id in Folder Knowledge and Knowledge-Base Attach Endpoints Summary Multiple endpoints accept a user-supplied file_id and attach the referenced file to a resource the caller cont…
| CVE ID | CVE-2026-45402 |
| Vendor | pip |
| Affected Product | open-webui |
| Vulnerability Type | Vulnerability |
| CVSS Score | 8.1 (HIGH) |
| Actively Exploited | ❌ No known exploitation |
| Patch Status | See Vendor Advisory → |
| Reported By | CYBERDUDEBIVASH SENTINEL APEX Intelligence (via github_advisories) |
file_id and attach the referenced file to a resource the caller controls (folder knowledge, knowledge-base contents) without verifying that the caller owns or has been granted access to the file. The file's content then becomes reachable through the downstream RAG / file-content paths, allowing any authenticated user to exfiltrate any other user's private file — and on the knowledge-base path, also to overwrite it — given knowledge of the file's UUID.folders.update backend/open_webui/routers/folders.py:156 — POST /api/v1/folders/{id}/update accepts a `FolderUpdaSigma rules, YARA signatures, IOC table, and SIEM queries for Splunk, Elastic, Sentinel, and Chronicle — deployable in 5 minutes.