Name:Abnormally High AWS Instances Terminated by User - MLTK id:1c02b86a-cd85-473e-a50b-014a9ac8fe3e version:5 date:2024-11-14 author:Jason Brewer, Splunk status:deprecated type:Anomaly Description:This search looks for AWS CloudTrail events where a user successfully terminates an abnormally high number of instances. This search is deprecated and have been translated to use the latest Change Datamodel. Data_source:
search:`cloudtrail` eventName=TerminateInstances errorCode=success `abnormally_high_aws_instances_terminated_by_user___mltk_filter` | bucket span=10m _time | stats count as instances_terminated by _time src_user | apply ec2_excessive_terminateinstances_v1 | rename "IsOutlier(instances_terminated)" as isOutlier | where isOutlier=1
how_to_implement:You must install the AWS App for Splunk (version 5.1.0 or later) and Splunk Add-on for AWS (version 4.4.0 or later), then configure your AWS CloudTrail inputs. The threshold value should be tuned to your environment. known_false_positives:Many service accounts configured within an AWS infrastructure are known to exhibit this behavior. Please adjust the threshold values and filter out service accounts from the output. Always verify if this search alerted on a human user. References: drilldown_searches:
: tags: analytic_story: - 'Suspicious AWS EC2 Activities' asset_type:AWS Instance mitre_attack_id: - 'T1078.004' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' security_domain:network
