Arbitrary file deletion

The Alertmanager in Grafana Enterprise Metrics before 1.2.1 and Metrics Enterprise 1.2.1 has a local file disclosure vulnerability when experimental.alertmanager.enable-api is used. The HTTP basic auth password_file can be used as an attack vector to send any file content via a webhook. The alertmanager templates can be used as an attack vector to send any file content because the alertmanager can load any text file specified in the templates list.