AWS RDS DB Instance Made Public

Last updated a month ago on 2025-11-24

Created 2 years ago on 2024-06-29

About

Identifies the creation or modification of an Amazon RDS DB instance or cluster where the "publiclyAccessible" attribute is set to "true". Publicly accessible RDS instances expose a network endpoint on the public internet, which may allow unauthorized access if combined with overly permissive security groups, weak authentication, or misconfigured IAM policies. Adversaries may enable public access on an existing instance, or create a new publicly accessible instance, to establish persistence, move data outside of controlled network boundaries, or bypass internal access controls.

Tags

Domain: CloudData Source: AWSData Source: Amazon Web ServicesData Source: AWS RDSUse Case: Threat DetectionTactic: PersistenceTactic: Defense EvasionLanguage: eql

Severity

medium

Risk Score

MITRE ATT&CK™

Persistence (TA0003)(external, opens in a new tab or window)

↳ Modify Authentication Process (T1556)(external, opens in a new tab or window)

Defense Evasion (TA0005)(external, opens in a new tab or window)

False Positive Examples

Public access is a common configuration used to enable access from outside a private VPC. Ensure that the instance should not be modified in this way before taking action.

License

Elastic License v2(external, opens in a new tab or window)

Definition

Rule Type: Event Correlation Rule
Integration Pack: Prebuilt Security Detection Rules
Index Patterns: filebeat-*logs-aws.cloudtrail-*
Related Integrations: aws(external, opens in a new tab or window)
Query

✄𐘗text code block:
✄𐘗any where event.dataset == "aws.cloudtrail"
    and event.provider == "rds.amazonaws.com"
    and event.outcome == "success"
    and (
        (event.action == "ModifyDBInstance" and stringContains(aws.cloudtrail.request_parameters, "publiclyAccessible=true"))
        or
        (event.action in ("CreateDBInstance", "CreateDBCluster") and stringContains(aws.cloudtrail.request_parameters, "publiclyAccessible=true"))
    )

Install detection rules in Elastic Security

Detect AWS RDS DB Instance Made Public in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(external, opens in a new tab or window).