Restore Public AWS RDS Instance

Status: test
Severity: high
Log source: product aws, service cloudtrail
Author: faloker
Source: github.com/SigmaHQ/sigma

Detects the recovery of a new public database instance from a snapshot. It may be a part of data exfiltration.

MITRE ATT&CK coverage

Tactic	Techniques
Exfiltration	`T1020` Automated Exfiltration

Telemetry coverage

Platform	Record / event type
AWS	CloudTrail event `RestoreDBInstanceFromDBSnapshot`: Creates a new DB instance from a DB snapshot.

Rules detecting the same action

These rules filter on the same operation.

AWS Public RDS Restore (Panther)
AWS RDS DB Instance Restored (Elastic)

Rule body

title: Restore Public AWS RDS Instance
id: c3f265c7-ff03-4056-8ab2-d486227b4599
status: test
description: Detects the recovery of a new public database instance from a snapshot. It may be a part of data exfiltration.
references:
    - https://github.com/RhinoSecurityLabs/pacu/blob/866376cd711666c775bbfcde0524c817f2c5b181/pacu/modules/rds__explore_snapshots/main.py
author: faloker
date: 2020-02-12
modified: 2022-10-09
tags:
    - attack.exfiltration
    - attack.t1020
logsource:
    product: aws
    service: cloudtrail
detection:
    selection_source:
        eventSource: rds.amazonaws.com
        responseElements.publiclyAccessible: 'true'
        eventName: RestoreDBInstanceFromDBSnapshot
    condition: selection_source
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: `condition`

selection_source

Stage 1: `selection_source`

selection_source:
    eventSource: rds.amazonaws.com
    responseElements.publiclyAccessible: 'true'
    eventName: RestoreDBInstanceFromDBSnapshot

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`eventName`	eq	`RestoreDBInstanceFromDBSnapshot`	`field:"aws::eventName" kind:eq value:"RestoreDBInstanceFromDBSnapshot"`
`eventSource`	eq	`rds.amazonaws.com`	`field:"aws::eventSource" kind:eq value:"rds.amazonaws.com"`
`responseElements.publiclyAccessible`	eq	`true`	`field:"responseElements.publiclyAccessible" kind:eq value:"true"`