paultyng / checkov

Prevent cloud misconfigurations during build time - Terraform static analysis

Checkov

Table of contents

• Description
• Features
• Screenshots
• Getting Started
• Support

Description

Checkov is a static code analysis tool for infrastructure-as-code. It scans cloud infrastructure provisioned using Terraform and detects security and compliance misconfigurations.

Checkov is written in Python and provides a simple method to write and manage policies. It follows the CIS Foundations benchmarks where applicable.

Features

• 60+ built-in policies cover security and compliance best practices for AWS, Azure & Google Cloud.
• Policies support evaluation of variables to their optional default value
• Supports in-line suppression of accepted risks or false-positives to reduce recurring scan failures.
• Output currently available as CLI, JSON or JUnit XML.

Screenshots

Scan results in CLI

Scheduled scan result in Jenkins

Getting started

Installation

pip install checkov

Configure an input folder

checkov -d /user/tf

Or a specific file

checkov -f /user/tf/example.tf

Scan result sample (CLI)

Passed Checks: 1, Failed Checks: 1, Suppressed Checks: 0
Check: "Ensure all data stored in the S3 bucket is securely encrypted at rest"
/main.tf:
	 Passed for resource: aws_s3_bucket.template_bucket 
Check: "Ensure all data stored in the S3 bucket is securely encrypted at rest"
/../regionStack/main.tf:
	 Failed for resource: aws_s3_bucket.sls_deployment_bucket_name       

Start using Checkov by reading the Getting Started page.

Using Docker

docker pull bridgecrew/checkov
docker run bridgecrew/checkov -i -v /user/tf:/tf -d /tf

Suppressing/Ignoring a check

Like any static-analysis tool it is limited by its analysis scope. For example, if a resource is managed manually, or using subsequent configuration management tooling, a suppression can be inserted as a simple code annotation.

Suppression comment format

To skip a check on a given Terraform definition block, apply the following comment pattern inside it's scope:

checkov:skip=<check_id>:<suppression_comment>

• <check_id> is one of the available check scanners
• <suppression_comment> is an optional suppression reason to be included in the output

Example

The following comment skip the CKV_AWS_20 check on the resource identified by foo-bucket, where the scan checks if an AWS S3 bucket is private. In the example, the bucket is configured with a public read access; Adding the suppress comment would skip the appropriate check instead of the check to fail.

resource "aws_s3_bucket" "foo-bucket" {
  region        = var.region
    #checkov:skip=CKV_AWS_20:The bucket is a public static content host
  bucket        = local.bucket_name
  force_destroy = true
  acl           = "public-read"
}

The output would now contain a SKIPPED check result entry:

...
...
Check: "S3 Bucket has an ACL defined which allows public access."
	SKIPPED for resource: aws_s3_bucket.foo-bucket
	Suppress comment: The bucket is a public static content host
	File: /example_skip_acl.tf:1-25
	
...

Alternatives

For Terraform compliance scanners check out tfsec, Terrascan and Terraform AWS Secure Baseline.

For CloudFormation scanning check out cfripper and cfn_nag.

Contributing

Contribution is welcomed!

Start by reviewing the contribution guidelines. After that, take a look at a good first issue.

Looking to contribute new checks? Learn how to write a new check (AKA policy) here

Support

Bridgecrew builds and maintains Checkov to make policy-as-code simple and accessible.

Start with our Documentation for quick tutorials and examples.

If you need direct support you can contact us at [email protected] or open a ticket.