Detectionmediumtest
Ingress/Egress Security Group Modification
Detects when an account makes changes to the ingress or egress rules of a security group. This can indicate that an attacker is attempting to open up new attack vectors in the account, that they are trying to exfiltrate data over the network, or that they are trying to allow machines in that VPC/Subnet to contact a C&C server.
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Log Source
AWScloudtrail
ProductAWS← raw: aws
Servicecloudtrail← raw: cloudtrail
Detection Logic
Detection Logic1 selector
detection:
selection:
eventSource: 'ec2.amazonaws.com'
eventName:
- 'AuthorizeSecurityGroupEgress'
- 'AuthorizeSecurityGroupIngress'
- 'RevokeSecurityGroupEgress'
- 'RevokeSecurityGroupIngress'
condition: selectionFalse Positives
New VPCs and Subnets being setup requiring a different security profile to those already defined
A single port being opened for a new service that is known to be deploying
Administrators closing unused ports to reduce the attack surface
References
MITRE ATT&CK
Tactics
Rule Metadata
Rule ID
6fb77778-040f-4015-9440-572aa9b6b580
Status
test
Level
medium
Type
Detection
Created
Thu Jul 11
Author
Path
rules/cloud/aws/cloudtrail/aws_cloudtrail_security_group_change_ingress_egress.yml
Raw Tags
attack.initial-accessattack.t1190