Auth bypass in Microsoft Simplechat
CVE-2026-57206
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.
Vulnerability class: Broken Authentication
EPSS: 0.010 (58.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L.
Affected products
- Microsoft Simplechat — versions < 0.241.206
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-57206?
- CVE-2026-57206 is a high-severity vulnerability in Microsoft Simplechat, classified under Missing Authentication for Critical Function. CVSS score: 8.6/10. Published 2026-07-16.
- How severe is CVE-2026-57206?
- High severity. CVSS v3 base score is 8.6 out of 10.