Slack anomaly event

slack

Classification:

attack

Set up the slack integration.

Goal

Detect when a Slack audit anomaly event is raised.

Strategy

This rule monitors Slack audit logs for when a Slack anomaly event is raised. Anomaly events are a special part of the Audit Logs API that help surface unexpected user behaviors. There will be a reason code published for any anomalous event. Anomalous events can include:

  • Excessive number of file downloads.
  • A Tor exit node was used.
  • Anomalous behaviour from an administrator account.

Triage and response

  1. Determine if the behaviour is expected by:
    • Contacting the user for more information.
    • Check for other signals and logs generated by the impacted user {{@usr.email}}, and look for deviations in the geolocation, ASN, or device properties.
  2. If the activity is deemed malicious:
    • Begin your organization’s incident response process and investigate.