What’s Vulnerable › Vulnerabilities

CVE-2026-57206: SimpleChat plugin validation endpoints missing authentication and authorization

• Severity: high (CVSS 8.6 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.0% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-16 · updated 2026-10-24
• Weakness: CWE-306

Description

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.

Affected products

• microsoft simplechat: before 0.241.206

References

• https://github.com/microsoft/simplechat/blob/main/docs/explanation/fixes/PLUGIN_VALIDATION_ROUTE_AUTH_FIX.md
• https://github.com/microsoft/simplechat/releases/tag/v0.250.001
• https://github.com/microsoft/simplechat/security/advisories/GHSA-g6gr-xp46-hrmj

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