Version Control Issues with Terraform

Unencrypted sensitive variables

The Problem

Storing sensitive information like access keys or passwords in plaintext within Terraform configurations poses a significant security risk. This practice can lead to unauthorized access and potential data breaches, especially when configurations are version-controlled in repositories.

Code Examples

Bad Practice

1variable "db_password" {
2  default = "supersecretpassword123"
3}
4
5resource "aws_db_instance" "default" {
6  engine         = "mysql"
7  engine_version = "5.7"
8  instance_class = "db.t3.micro"
9  name           = "mydb"
10  username       = "admin"
11  password       = var.db_password
12}

‍

Good Practice

variable "db_password" {
  type = string
}

resource "aws_db_instance" "default" {
  engine         = "mysql"
  engine_version = "5.7"
  instance_class = "db.t3.micro"
  name           = "mydb"
  username       = "admin"
  password       = var.db_password
}

Secure Patterns

To mitigate the risk of exposing sensitive variables:

• Use environment variables or secure secret management systems to inject sensitive data.
• Implement Terraform's built-in encryption for state files.
• Utilize AWS Secrets Manager or HashiCorp Vault for storing and retrieving secrets.
• Never commit sensitive information directly in Terraform configuration files.

‍

Git-ignored crucial security configurations

The Problem

Ignoring important security configurations in version control can lead to inconsistent and potentially insecure infrastructure deployments. This issue often stems from attempts to keep sensitive information out of repositories but can result in missing critical security settings.

Code Examples

Bad Practice

# .gitignore
*.tfvars
security_groups.tf

‍‍

Good Practice

1# .gitignore
2*.tfvars
3!example.tfvars

‍

Secure Patterns

To ensure crucial security configurations are version-controlled:

• Version control all Terraform configuration files, including security-related ones.
• Use placeholder files or templates for sensitive configurations.
• Implement a secure process for managing and applying sensitive data separately.
• Regularly audit Git-ignored files to ensure no critical configurations are excluded.

‍

Outdated provider versions with known vulnerabilities

The Problem

Using outdated provider versions can expose your infrastructure to known vulnerabilities and compatibility issues. This problem is often exacerbated by a lack of regular updates and version pinning best practices.

Code Examples

Bad Practice

terraform {
  required_providers {
    aws = {
      source = "hashicorp/aws"
    }
  }
}

provider "aws" {
  region = "us-west-2"
}

‍

Good Practice

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 4.16"
    }
  }
  required_version = ">= 1.2.0"
}

provider "aws" {
  region = "us-west-2"
}

‍

Secure Patterns

To manage provider versions securely:

• Implement version constraints for all providers used in your Terraform configurations.
• Regularly review and update provider versions to incorporate security patches.
• Use semantic versioning to manage breaking changes and updates.
• Implement a process for testing provider updates before applying them to production environments.

‍

Practical Remediation Steps

1. Immediate Actions

• Conduct a comprehensive audit of Terraform configurations to identify and encrypt sensitive variables.
• Review Git-ignored files and ensure all crucial security configurations are version-controlled.
• Update all provider versions to the latest stable releases, addressing any known vulnerabilities.
• Implement Terraform's dependency lock file (terraform.lock.hcl) to manage provider versions consistently across environments.

2. Long-term Strategy

• Implement security automation using tools like Gomboc AI
• Develop and enforce a version control policy for Terraform configurations, including guidelines for managing sensitive data and security configurations.
• Set up comprehensive monitoring and alerting for Terraform operations
• Conduct regular security audits of Terraform configurations
• Provide ongoing security training for team members working with Terraform and cloud resource

By addressing these common pitfalls and implementing secure practices, platform engineers can significantly enhance the security posture of their Terraform-managed infrastructure. Remember, security is an ongoing process that requires constant vigilance and adaptation to new threats and best practices.

Terraform has become an essential tool for managing cloud infrastructure as code. However, with great power comes great responsibility, especially when it comes to access management and authentication. In this guide, we'll explore common pitfalls and provide secure solutions to help platform engineers enhance their Terraform security posture.