anomalous_traffic_s3
Explanation
This event is triggered by Netography's Fusion Portal when it detects a data transfer to Amazon S3 that exceeds an automatically determined baseline threshold. Auto Thresholding observes related network traffic to determine a baseline and then defines thresholds as a number of standard deviations from the typically observed traffic. This event specifically looks for data transfers to S3 that are multiple standard deviations greater than the learned baseline.
What to Look For
Anomalous traffic to S3 may be an indication that your network is compromised and attackers are stealing information by moving it (exfiltrating it) off your network. Attackers frequently exfiltrate data using S3 (Amazon Simple Storage Service) because it is a low-cost, highly available cloud storage service. Detections of anomalous traffic to S3 are worthy of investigation because they may be indicative of a ransomware attack or industrial espionage.
Investigate hosts that are the source of this sort of activity in order to make sure that it is authorized and expected, and the hosts have not been compromised. Ensure that hosts sending data to Amazon S3 are authorized to send data into a public cloud and that they are storing data in an approved destination S3 bucket. Check network logs for additional information to ensure that sensitive information is secure.
Related MITRE ATT&CK Categories
Updated about 2 months ago