AWS network ACL rule creation

Synopsis

Field	Value
Activation Period	14 Days
Training Period	30 Days
Test Period	N/A (single event)
Deduplication Period	1 Day
Required Data	AWS Audit Log
Detection Modules	Cloud
ATT&CK Tactic	Persistence (TA0003), Exfiltration (TA0010)
ATT&CK Technique	External Remote Services (T1133), Exfiltration Over Alternative Protocol (T1048)
Severity	Informational

Description

An AWS network ACL rule was created with a specific rule number.

Attacker's Goals

Deleting an ingress rule may allow an attacker to gain persistence in the cloud environment. Deleting an egress rule may enable data exfiltration.

Investigative actions

• Check the VPC affected by this change.
• Verify the rule number (as rules are applied in order).
• Determine whether the rule is ingress or egress.