Elastic Security Detection Rules

AWS Systems Manager SecureString Parameter Request with Decryption Flag

Last updated 5 months ago on 2025-01-27
Created a year ago on 2024-04-12

About

Detects the first occurrence of a user identity accessing AWS Systems Manager (SSM) SecureString parameters using the GetParameter or GetParameters API actions with credentials in the request parameters. This could indicate that the user is accessing sensitive information. This rule detects when a user accesses a SecureString parameter with the `withDecryption` parameter set to true. This is a [NewTerms](https://www.elastic.co/guide/en/security/current/rules-ui-create.html#create-new-terms-rule) rule that detects the first occurrence of a specific AWS ARN accessing SecureString parameters with decryption within the last 10 days.
Tags
Domain: CloudData Source: AWSData Source: Amazon Web ServicesData Source: AWS Systems ManagerTactic: Credential AccessLanguage: kuery
Severity
medium
Risk Score
47
MITRE ATT&CK™

Credential Access (TA0006)(opens in a new tab or window)

↳ Credentials from Password Stores (T1555)(opens in a new tab or window)

False Positive Examples
Users may legitimately access AWS Systems Manager (SSM) parameters using the GetParameter, GetParameters, or DescribeParameters API actions with credentials in the request parameters. Ensure that the user has a legitimate reason to access the parameters and that the credentials are secured.
License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
New Terms Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
filebeat-*logs-aws.cloudtrail-*
Related Integrations

aws(opens in a new tab or window)

Query
event.dataset: aws.cloudtrail
    and event.provider: "ssm.amazonaws.com"
    and event.action: (GetParameters or GetParameter)
    and event.outcome: success
    and aws.cloudtrail.flattened.request_parameters.withDecryption: true
    and not source.address: (
        "cloudformation.amazonaws.com" or
        "servicecatalog.amazonaws.com"
    )

Install detection rules in Elastic Security

Detect AWS Systems Manager SecureString Parameter Request with Decryption Flag 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(opens in a new tab or window).