CVE-2026-45402
8.1 · HIGHOverview
CVE-2026-45402 is a high-severity vulnerability affecting openwebui open_webui. It was published on May 15, 2026 and has a CVSS 3.1 base score of 8.1 (HIGH).
This vulnerability has a CVSS 3.1 base score of 8.1, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, multiple endpoints accept a user-supplied 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. This affects backend/open_webui/routers/folders.py (POST /api/v1/folders/{id}/update), backend/open_webui/routers/knowledge.py (add_file_to_knowledge_by_id), and backend/open_webui/routers/knowledge.py (add_files_to_knowledge_by_id_batch). This vulnerability is fixed in 0.9.5.
Remediation
Check the references section for vendor advisories and patches from openwebui. Update open_webui to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| openwebui | open_webui | >= 0, < 0.9.5 | Affected |
Frequently Asked Questions
What is CVE-2026-45402?
CVE-2026-45402 is a high-severity vulnerability affecting openwebui open_webui. It was published on May 15, 2026 and has a CVSS 3.1 base score of 8.1 (HIGH).
How severe is CVE-2026-45402?
This vulnerability has a CVSS 3.1 base score of 8.1, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-45402?
Check the references section for vendor advisories and patches from openwebui. Update open_webui to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-45402?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-45402 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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