This is an outlier type of alert which presents the abnormal spikes in outbound traffic leaving the company network towards an untrusted zone.
MITRE ATT&CK Tactics
Firewall Traffic Logs
Asset Inventory Application scanners
(if organization is not blocking outbound traffic in perimeter firewall)
1. Review configuration of the internal machine(s) that is/are generating this traffic.
2. Run a EDR scan on the internal host
3. If applicable, quarantine or disconnect the machine from the internal network
4. Review perimeter firewall logs for indicators of large data transferred from internal machine to internet destinations (data leakage)