Name:Abnormally High AWS Instances Launched by User - MLTK id:dec41ad5-d579-42cb-b4c6-f5dbb778bbe5 version:4 date:2024-10-17 author:Jason Brewer, Splunk status:deprecated type:Anomaly Description:This search looks for AWS CloudTrail events where a user successfully launches 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=RunInstances errorCode=success `abnormally_high_aws_instances_launched_by_user___mltk_filter` | bucket span=10m _time | stats count as instances_launched by _time src_user | apply ec2_excessive_runinstances_v1 | rename "IsOutlier(instances_launched)" 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: - 'AWS Cryptomining' - 'Suspicious AWS EC2 Activities' asset_type:AWS Instance confidence:50 impact:50 message:tbd mitre_attack_id: - 'T1078.004' observable: name:'src_user' type:'User' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'eventName' - 'errorCode' - 'src_user' risk_score:25.0 security_domain:network
