AWS EC2 Network Access Control List Deletion

Identifies the deletion of an Amazon Elastic Compute Cloud (EC2) network access control list (ACL) or one of its ingress/egress entries.

Rule type: query

Rule indices:

• filebeat-*
• logs-aws*

Severity: medium

Risk score: 47

Runs every: 10m

Searches indices from: now-60m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

• https://awscli.amazonaws.com/v2/documentation/api/latest/reference/ec2/delete-network-acl.html
• https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DeleteNetworkAcl.html
• https://awscli.amazonaws.com/v2/documentation/api/latest/reference/ec2/delete-network-acl-entry.html
• https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DeleteNetworkAclEntry.html

Tags:

• Elastic
• Cloud
• AWS
• Continuous Monitoring
• SecOps
• Network Security

Version: 7

Rule authors:

• Elastic

Rule license: Elastic License v2

The AWS Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule.

event.dataset:aws.cloudtrail and event.provider:ec2.amazonaws.com and event.action:(DeleteNetworkAcl or DeleteNetworkAclEntry) and event.outcome:success

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Defense Evasion
  • ID: TA0005
  • Reference URL: https://attack.mitre.org/tactics/TA0005/

• Technique:

  • Name: Impair Defenses
  • ID: T1562
  • Reference URL: https://attack.mitre.org/techniques/T1562/

• Sub-technique:

  • Name: Disable or Modify Tools
  • ID: T1562.001
  • Reference URL: https://attack.mitre.org/techniques/T1562/001/