S3 Bucket ACL Allows Read Or Write to All Users

  • Query id: 38c5ee0d-7f22-4260-ab72-5073048df100
  • Query name: S3 Bucket ACL Allows Read Or Write to All Users
  • Platform: Terraform
  • Severity: Critical
  • Category: Access Control
  • CWE: 732
  • URL: Github

Description

S3 Buckets should not be readable and writable to all users
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - tf file
provider "aws" {
  region = "us-east-1"
}

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 3.0"
    }
  }
}
resource "aws_s3_bucket" "positive1" {
  bucket = "my-tf-test-bucket"
  acl    = "public-read"

  tags = {
    Name        = "My bucket"
    Environment = "Dev"
  }

  versioning {
    enabled = true
  }
}
Positive test num. 2 - tf file
provider "aws" {
  region = "us-east-1"
}

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 3.0"
    }
  }
}

resource "aws_s3_bucket" "positive2" {
  bucket = "my-tf-test-bucket"
  acl    = "public-read-write"

  tags = {
    Name        = "My bucket"
    Environment = "Dev"
  }

  versioning {
    enabled = true
  }
}
Positive test num. 3 - tf file
module "s3_bucket" {
  source = "terraform-aws-modules/s3-bucket/aws"
  version = "3.7.0"

  bucket = "my-s3-bucket"
  acl    = "public-read"

  versioning = {
    enabled = true
  }
}

Positive test num. 4 - tf file 
module "s3_bucket" {
  source = "terraform-aws-modules/s3-bucket/aws"
  version = "3.7.0"

  bucket = "my-s3-bucket"
  acl    = "public-read-write"

  versioning = {
    enabled = true
  }
}
Positive test num. 5 - tf file 
provider "aws" {
  region = "us-east-1"
}

terraform {
  required_providers {
    aws = {
      source = "hashicorp/aws"
      version = "4.2.0"
    }
  }
}

resource "aws_s3_bucket" "example00" {
  bucket = "my-tf-example-bucket"
}

resource "aws_s3_bucket_acl" "example_bucket_acl" {
  bucket = aws_s3_bucket.example00.id
  acl    = "public-read"
}
Positive test num. 6 - tf file 
provider "aws" {
  region = "us-east-1"
}

terraform {
  required_providers {
    aws = {
      source = "hashicorp/aws"
      version = "4.2.0"
    }
  }
}

resource "aws_s3_bucket" "example000" {
  bucket = "my-tf-example-bucket"
}

resource "aws_s3_bucket_acl" "example_bucket_acl" {
  bucket = aws_s3_bucket.example000.id
  acl    = "public-read-write"
}

Code samples without security vulnerabilities

Negative test num. 1 - tf file
provider "aws" {
  region = "us-east-1"
}

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 3.0"
    }
  }
}

resource "aws_s3_bucket" "negative1" {
  bucket = "my-tf-test-bucket"
  acl    = "private"

  tags = {
    Name        = "My bucket"
    Environment = "Dev"
  }

  versioning {
    enabled = true
  }
}
Negative test num. 2 - tf file
module "s3_bucket" {
  source = "terraform-aws-modules/s3-bucket/aws"
  version = "3.7.0"

  bucket = "my-s3-bucket"
  acl    = "private"

  versioning = {
    enabled = true
  }
}
Negative test num. 3 - tf file
provider "aws" {
  region = "us-east-1"
}

terraform {
  required_providers {
    aws = {
      source = "hashicorp/aws"
      version = "4.2.0"
    }
  }
}

resource "aws_s3_bucket" "example0" {
  bucket = "my-tf-example-bucket"
}

resource "aws_s3_bucket_acl" "example_bucket_acl" {
  bucket = aws_s3_bucket.example0.id
  acl    = "private"
}