Grafana Alerting Editors can edit destination of webhooks they did not create

In Grafana's alerting system, users with edit permissions for a contact point, specifically the permissions “alert.notifications:write” or “alert.notifications.receivers:test” that are granted as part of the fixed role "Contact Point Writer", which is part of the basic role Editor - can edit contact points created by other users, modify the endpoint URL to a controlled server. By invoking the test functionality, attackers can capture and extract redacted secure settings, such as authentication credentials for third-party services (e.g., Slack tokens). This leads to unauthorized access and potential compromise of external integrations.