CVE-2026-109285: Open WebUI 0.6.0 before 0.11.4 Improper Access Control via Stale File Metadata
Open WebUI from 0.6.0 before 0.11.4 contains an improper access control vulnerability in hasaccesstofile that lets former knowledge base collaborators keep file access via stale cached knowledge base references. Attackers with read or write grants can download removed files through the file content endpoint or delete them, including from the owner's private knowledge bases.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Open WebUIto a version that resolves this vulnerability.Fixed in 0.11.4
Event History
Frequently Asked Questions
Who can exploit this issue?
A former collaborator who previously had read or write access to a knowledge base can exploit it after their access should have been removed. The issue can also affect files in the knowledge base owner's private knowledge bases.
What access and conditions are required?
The attacker needs an existing read or write grant and stale cached knowledge base references associated with files. Exploitation is performed through the file content endpoint and does not require user interaction.
What could an attacker do?
An affected former collaborator can download files that were removed from their authorized access scope. They may also delete those files, affecting confidentiality, integrity, and availability.
Which versions are affected?
Open WebUI versions from 0.6.0 before 0.11.4 are affected. Version 0.11.4 is not included in the affected range.