Authentication Bypass in Open WebUI AI Platform by Open WebUI
CVE-2026-45402

8.1HIGH

Key Information:

Vendor

Open-webui

Status
Open-webui
Vendor
CVE Published:
15 May 2026

What is CVE-2026-45402?

Open WebUI, a self-hosted AI platform, has a vulnerability in versions prior to 0.9.5 where multiple endpoints fail to properly verify user permissions for file access. This allows authenticated users to access and exfiltrate files owned by others through misuse of file identifiers. Specifically, users can manipulate file references to gain access to sensitive information or overwrite files within the knowledge base. This security flaw underscores the importance of rigorous access controls in application design and has been addressed in version 0.9.5.

Affected Version(s)

open-webui < 0.9.5

References

https://github.com/open-webui/open-webui/security/advisor...
x_refsource_CONFIRM

CVSS V3.1

Score:
8.1
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.