Description
Blueprint Studio is a VS Code-like file editor for Home Assistant configuration files. Prior to 2.5.2, Blueprint Studio exposed administrator-intended backend API actions to any authenticated Home Assistant user because the backend did not consistently enforce the panel's admin-only authorization boundary. Affected surfaces included the backend API, upload API, stream routes, terminal WebSocket, Blueprint Studio WebSocket subscriptions, call_service, render_template, global_replace, file and stream access paths, upload handling, and terminal helpers. A non-admin user could invoke arbitrary Home Assistant services, expose Home Assistant state through templates, modify configuration files, access streamed or downloaded configuration content, upload files, or reach terminal-related helpers. These actions could compromise the confidentiality, integrity, and availability of the Home Assistant installation. This issue is fixed in version 2.5.2.
References3
Metrics
- CVSS 4.0
-
8.7
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 40 · as of 11 November 2026
- CWE
- CWE-862
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