CVE-2026-58201: Merill Lokka

High severity, CVSS 8.7. EPSS: 0.5% chance of exploitation in the next 30 days.

Lokka is a Model Context Protocol server for Microsoft 365, including Microsoft Graph and other services. Prior to 2.1.2, the Lokka-Microsoft tool in src/mcp/src/main.ts uses direct URL string concatenation to append the user-controlled path value to the management.azure.com base URL. A specially crafted path can alter URL authority parsing and cause an Azure Resource Manager bearer token to be sent to an unintended host. This issue is fixed in version 2.1.2.

Affected products

• Merill Lokka: before 2.1.2 (fixed in 2.1.2)

Published 2026-09-15. Last modified 2026-09-30.