Detection: Lambda Function Granted Public Access

Overview

Detect when an AWS Lambda function was granted public access. Publicly accessible functions expose workloads to unauthorized invocations, increasing the risk of malicious exploitation, data breaches, or resource abuse. Restricting access to trusted users, roles, and services ensures security and cost efficiency.

References:

Usage

Run the detection in your terminal:

powerpipe detection run aws_cloudtrail_log_detections.detection.lambda_function_granted_public_access

Snapshot and share results via Turbot Pipes:

powerpipe login
powerpipe detection run aws_cloudtrail_log_detections.detection.lambda_function_granted_public_access --share

SQL

This detection uses a named query:

select
  tp_timestamp as timestamp,
string_split(event_source, '.')[1] || ':' || event_name as operation,
request_parameters ->> 'functionName' as resource,
user_identity.arn as actor,
tp_source_ip as source_ip,
tp_index as account_id,
aws_region as region,
tp_id as source_id,
*

from
  aws_cloudtrail_log
where
  event_source = 'lambda.amazonaws.com'
  and event_name like 'AddPermission%'
  and (request_parameters ->> 'principal') = '*'
  and error_code is null

order by
  event_time desc;

Detection: Lambda Function Granted Public Access

Overview

Usage

SQL

Tags