🛡️ AWS EC2 Default Security Group does not restrict all traffic🟢
- Contextual name: 🛡️ Default Security Group does not restrict all traffic🟢
- ID:
/ce/ca/aws/ec2/default-security-group-does-not-restrict-all-traffic - Tags:
- Policy Type:
COMPLIANCE_POLICY - Policy Categories:
SECURITY
Logic
Similar Policies
- Cloud Conformity: Default Security Group Unrestricted
- Internal:
dec-x-ecd99f88
Similar Internal Rules
| Rule | Policies | Flags |
|---|---|---|
| ✉️ dec-x-ecd99f88 | 1 |
Description
Description
A VPC comes with a default security group whose initial settings deny all inbound traffic, allow all outbound traffic, and allow all traffic between instances assigned to the security group. If you don't specify a security group when you launch an instance, the instance is automatically assigned to this default security group. Security groups provide stateful filtering of ingress/egress network traffic to AWS resources. It is recommended that the default security group restrict all traffic.
The default VPC in every region should have its default security group updated to comply with the following:
- No inbound rules.s
- No outbound rules.
NOTE: When implementing this recommendation, VPC flow logging is invaluable in determining the least privilege port access required by systems to work properly because it can log all packet acceptances and rejections occurring under the current security groups. This dramatically reduces the primary barrier to least privilege engineering - discovering the minimum ports required by systems in the environment. Even if the VPC flow logging recommendation in this benchmark is not adopted as a permanent security measure, it should be used during any period of discovery and engineering for least privileged security groups.
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Remediation
Remediation
Security Group Members
Perform the following to implement the prescribed state:
- Identify AWS resources that exist within the default security group.
- Create a set of least privilege security groups for those resources.
- Place the resources in those security groups.
- Remove the resources noted in #1 from the default security group.
Security Group State
Login to the AWS Management Console at https://console.aws.amazon.com/vpc/home.
Repeat the next steps for all VPCs - including the default VPC in each AWS region:
In the left pane, click
Security Groups.For each default security group, perform the following:
- Select the
defaultsecurity group.- Click the
Inbound Rulestab.- Remove any inbound rules.
- Click the
Outbound Rulestab.- Remove any Outbound rules.
Recommended
IAM groups allow you to edit the
namefield. After remediating default groups rules for all VPCs in all regions, edit this field to add text similar toDO NOT USE. DO NOT ADD RULES.