Name:ASL AWS Disable Bucket Versioning id:f32598bb-fa5f-4afd-8ab3-0263cc28efbc version:1 date:2024-12-16 author:Patrick Bareiss, Splunk status:production type:Anomaly Description:The following analytic detects when AWS S3 bucket versioning is suspended by a user. It leverages AWS CloudTrail logs to identify `PutBucketVersioning` events with the `VersioningConfiguration.Status` set to `Suspended`. This activity is significant because disabling versioning can prevent recovery of deleted or modified data, which is a common tactic in ransomware attacks. If confirmed malicious, this action could lead to data loss and hinder recovery efforts, severely impacting data integrity and availability. Data_source:
-ASL AWS CloudTrail
search:`amazon_security_lake` api.operation=PutBucketVersioning | spath input=api.request.data path=VersioningConfiguration.Status output=Status | spath input=api.request.data path=bucketName output=bucketName | search Status=Suspended | fillnull | stats count min(_time) as firstTime max(_time) as lastTime by api.operation actor.user.uid actor.user.account.uid http_request.user_agent src_endpoint.ip cloud.region api.request.data bucketName | rename actor.user.uid as user, src_endpoint.ip as src_ip, cloud.region as region, http_request.user_agent as user_agent | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`| `asl_aws_disable_bucket_versioning_filter`
how_to_implement:The detection is based on Amazon Security Lake events from Amazon Web Services (AWS), which is a centralized data lake that provides security-related data from AWS services. To use this detection, you must ingest CloudTrail logs from Amazon Security Lake into Splunk. To run this search, ensure that you ingest events using the latest version of Splunk Add-on for Amazon Web Services (https://splunkbase.splunk.com/app/1876) or the Federated Analytics App. known_false_positives:It is possible that an AWS Administrator has legitimately disabled versioning on certain buckets to avoid costs. References: -https://invictus-ir.medium.com/ransomware-in-the-cloud-7f14805bbe82 -https://bleemb.medium.com/data-exfiltration-with-native-aws-s3-features-c94ae4d13436 drilldown_searches: name:'View the detection results for - "$user$"' search:'%original_detection_search% | search user = "$user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$") starthoursago=168 | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' tags: analytic_story: - 'Suspicious AWS S3 Activities' - 'Data Exfiltration' asset_type:AWS Account confidence:80 impact:80 message:Bucket Versioning is suspended for S3 buckets- $bucketName$ by user $user$ from IP address $src_ip$ mitre_attack_id: - 'T1490' observable: name:'user' type:'User' - role: - 'Victim' name:'src_ip' type:'IP Address' - role: - 'Attacker' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - 'api.operation' - 'actor.user.uid' - 'actor.user.account.uid' - 'api.request.data' - 'http_request.user_agent' - 'src_endpoint.ip' - 'src_endpoint.domain' - 'cloud.region' risk_score:64 security_domain:threat
