Is CVE-2026-45402 actively exploited?

No active exploitation of CVE-2026-45402 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-45402 be exploited remotely?

Yes. CVE-2026-45402 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-45402?

CVE-2026-45402 has a CVSS score of 8.1 (HIGH).

HOME VULNERABILITIESCVE-2026-45402

HIGH

CVE-2026-45402

CWE-639Published: May 15, 2026· Updated: May 18, 2026

8.1

CVSS v3.1

EPSS:0.03%probability of exploitation in 30 daysPercentile:9.1th

Official 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.

NVD Source

Technical Analysis

CVE-2026-45402 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), with a CVSS base score of 8.1.