S3 Bucket Access to Any Principal
- Query id: 7af43613-6bb9-4a0e-8c4d-1314b799425e
- Query name: S3 Bucket Access to Any Principal
- Platform: Terraform
- Severity: High
- Category: Access Control
- URL: Github
Description¶
S3 Buckets must not allow Actions From All Principals, as to prevent leaking private information to the entire internet or allow unauthorized data tampering / deletion. This means the 'Effect' must not be 'Allow' when there are All Principals
Documentation
Code samples¶
Code samples with security vulnerabilities¶
Postitive test num. 1 - tf file
resource "aws_s3_bucket_policy" "positive1" {
bucket = aws_s3_bucket.b.id
policy = <<POLICY
{
"Version": "2012-10-17",
"Id": "MYBUCKETPOLICY",
"Statement": [
{
"Sid": "IPAllow",
"Effect": "Allow",
"Principal": {
"AWS": "*"
},
"Action": "s3:*",
"Resource": "arn:aws:s3:::my_tf_test_bucket/*",
"Condition": {
"IpAddress": {"aws:SourceIp": "8.8.8.8/32"}
}
}
]
}
POLICY
}
Postitive 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
}
policy = <<POLICY
{
"Version": "2012-10-17",
"Id": "MYBUCKETPOLICY",
"Statement": [
{
"Sid": "IPAllow",
"Effect": "Allow",
"Principal": {
"AWS": "*"
},
"Action": "s3:*",
"Resource": "arn:aws:s3:::my_tf_test_bucket/*",
"Condition": {
"IpAddress": {"aws:SourceIp": "8.8.8.8/32"}
}
}
]
}
POLICY
}
Code samples without security vulnerabilities¶
Negative test num. 1 - tf file
resource "aws_s3_bucket_policy" "negative1" {
bucket = aws_s3_bucket.b.id
policy = <<POLICY
{
"Version": "2012-10-17",
"Id": "MYBUCKETPOLICY",
"Statement": [
{
"Sid": "IPAllow",
"Effect": "Deny",
"Action": "s3:*",
"Resource": "arn:aws:s3:::my_tf_test_bucket/*",
"Condition": {
"IpAddress": {"aws:SourceIp": "8.8.8.8/32"}
}
}
]
}
POLICY
}
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
}
policy = <<POLICY
{
"Version": "2012-10-17",
"Id": "MYBUCKETPOLICY",
"Statement": [
{
"Sid": "IPAllow",
"Effect": "Deny",
"Action": "s3:*",
"Resource": "arn:aws:s3:::my_tf_test_bucket/*",
"Condition": {
"IpAddress": {"aws:SourceIp": "8.8.8.8/32"}
}
}
]
}
POLICY
}