Windmill versions 1.56.0 through 1.614.0 contain a missing authorization vulnerability that allows users with the Operator role to perform prohibited entity creation and modification actions via the backend API. Although Operators are documented and priced as unable to create or modify entities, the API does not enforce the Operator restriction on workspace endpoints, allowing an Operator to create and update scripts, flows, apps, and raw_apps. Since Operators can also execute scripts via the jobs API, this allows direct privilege escalation to remote code execution within the Windmill deployment.
This vulnerability has existed since the introduction of the Operator role in version 1.56.0.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
References 6
https://apps.nextcloud.com/apps/flow/releases
disclosure@vulncheck.com
https://chocapikk.com/posts/2026/windfall-nextcloud-flow-windmill-rce/
disclosure@vulncheck.com
https://github.com/Chocapikk/Windfall
disclosure@vulncheck.com
https://github.com/windmill-labs/windmill/commit/c621a74804f4f6e8318819c01e3a23…
disclosure@vulncheck.com
https://github.com/windmill-labs/windmill/releases/tag/v1.615.0
disclosure@vulncheck.com
https://www.windmill.dev/
disclosure@vulncheck.com