diff --git a/detections/cloud/detect_shared_ec2_snapshot.yml b/detections/cloud/detect_shared_ec2_snapshot.yml index d6e6f9c1b8..19fd4a8cdd 100644 --- a/detections/cloud/detect_shared_ec2_snapshot.yml +++ b/detections/cloud/detect_shared_ec2_snapshot.yml @@ -5,16 +5,18 @@ date: '2021-07-20' author: Bhavin Patel, Splunk type: batch datamodel: [] -description: This search looks for AWS CloudTrail events where an EC2 snapshot permissions are modified to be shared with a different AWS account. -search: '`cloudtrail` eventName=ModifySnapshotAttribute | rename requestParameters.createVolumePermission.add.items{}.userId as requested_account_id | search requested_account_id != NULL -| eval match=if(requested_account_id==aws_account_id,"Match","No Match") -| table _time user_arn src_ip requestParameters.attributeType requested_account_id aws_account_id match vendor_region user_agent | where match = "No Match" - | `detect_shared_ec2_snapshot_filter` ' +description: This search looks for AWS CloudTrail events where an EC2 snapshot permissions + are modified to be shared with a different AWS account. +search: '`cloudtrail` eventName=ModifySnapshotAttribute | rename requestParameters.createVolumePermission.add.items{}.userId + as requested_account_id | search requested_account_id != NULL | eval match=if(requested_account_id==aws_account_id,"Match","No + Match") | table _time user_arn src_ip requestParameters.attributeType requested_account_id + aws_account_id match vendor_region user_agent | where match = "No Match" | `detect_shared_ec2_snapshot_filter` ' how_to_implement: You must install splunk AWS add on and Splunk App for AWS. This search works with AWS CloudTrail logs. -known_false_positives: It is possible that an AWS admin has legitimately shared a snapshot with others for a specific purpose. -references: - - https://labs.nettitude.com/blog/how-to-exfiltrate-aws-ec2-data/ +known_false_positives: It is possible that an AWS admin has legitimately shared a + snapshot with others for a specific purpose. +references: +- https://labs.nettitude.com/blog/how-to-exfiltrate-aws-ec2-data/ tags: analytic_story: - Suspicious Cloud Instance Activities @@ -40,14 +42,12 @@ tags: - eventName - user_arn - src_ip - - requestParameters.attributeType - - aws_account_id - - vendor_region - - user_agent - + - requestParameters.attributeType + - aws_account_id + - vendor_region + - user_agent impact: 60 confidence: 80 - # (impact * confidence)/100 risk_score: 48 context: - Source:Cloud Data @@ -55,7 +55,8 @@ tags: - Outcome:Allowed - Stage:Execution - Stage:Exfiltration - message: AWS EC2 snapshot from account $aws_account_id$ is shared with $requested_account_id$ by user $user_arn$ from $src_ip$ + message: AWS EC2 snapshot from account $aws_account_id$ is shared with $requested_account_id$ + by user $user_arn$ from $src_ip$ observable: - name: user_arn type: User @@ -65,4 +66,7 @@ tags: type: IP Address role: - Attacker - security_domain: threat \ No newline at end of file + security_domain: threat + automated_detection_testing: passed + dataset: + - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1537/aws_snapshot_exfil/aws_cloudtrail_events.json