CVE-2026-57206: high-severity vulnerability in microsoft simplechat
SimpleChat plugin validation endpoints missing authentication and authorization
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.6epss 1.0%
SimpleChat is a secure AI conversation application with personal and group workspaces for document-grounded interactions. Prior to 0.241.206, several plugin validation routes in application/single_app/plugin_validation_endpoint.py, including `POST /api/admin/plugins/test-instantiation`, `GET /api/admin/plugins/health-check/<plugin_name>`, `POST /api/admin/plugins/repair/<plugin_name>`, and `POST /api/plugins/validate`, relied on @swagger_route(security=get_auth_security()) documentation without enforcing @login_required, @user_required, or @admin_required at runtime, allowing unauthenticated or unauthorized clients to invoke plugin validation, health, and repair behavior. This issue is fixed in version 0.241.206.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L
Affected products
microsoft · simplechatRelated CVEs — microsoft simplechat
In the same product, most dangerous first.
CVE-2026-57205MEDIUMSimpleChat: Authenticated users can access other users' profile metadata through user IDOR endpointsEPSS 0.9%CVE-2026-105797HIGHSimpleChat: Command injection via authorization-gate ordering flaw (arbitrary process spawn through MCP stdio transport)EPSS 0.6%CVE-2026-105798HIGHSimpleChat: Stored XSS via group document filename in inline onclick handlerEPSS 0.5%