Name:Detect new API calls from user roles id:22773e84-bac0-4595-b086-20d3f335b4f1 version:3 date:2024-10-17 author:Bhavin Patel, Splunk status:deprecated type:Anomaly Description:This search detects new API calls that have either never been seen before or that have not been seen in the previous hour, where the identity type is `AssumedRole`. Data_source:
search:`cloudtrail` eventType=AwsApiCall errorCode=success userIdentity.type=AssumedRole [search `cloudtrail` eventType=AwsApiCall errorCode=success userIdentity.type=AssumedRole | stats earliest(_time) as earliest latest(_time) as latest by userName eventName | inputlookup append=t previously_seen_api_calls_from_user_roles | stats min(earliest) as earliest, max(latest) as latest by userName eventName | outputlookup previously_seen_api_calls_from_user_roles| eval newApiCallfromUserRole=if(earliest>=relative_time(now(), "-70m@m"), 1, 0) | where newApiCallfromUserRole=1 | `security_content_ctime(earliest)` | `security_content_ctime(latest)` | table eventName userName] |rename userName as user| stats values(eventName) earliest(_time) as earliest latest(_time) as latest by user | `security_content_ctime(earliest)` | `security_content_ctime(latest)` | `detect_new_api_calls_from_user_roles_filter`
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. This search works best when you run the "Previously seen API call per user roles in AWS CloudTrail" support search once to create a history of previously seen user roles. known_false_positives:It is possible that there are legitimate user roles making new or infrequently used API calls in your infrastructure, causing the search to trigger. References: drilldown_searches:
: tags: analytic_story: - 'AWS User Monitoring' asset_type:AWS Instance confidence:50 impact:50 message:tbd mitre_attack_id: - 'T1078.004' observable: name:'user' type:'User' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'eventType' - 'errorCode' - 'userIdentity.type' - 'userName' - 'eventName' risk_score:25.0 security_domain:endpoint
