Security Groups With Exposed Admin Ports
- Query id: cdbb0467-2957-4a77-9992-7b55b29df7b7
- Query name: Security Groups With Exposed Admin Ports
- Platform: CloudFormation
- Severity: High
- Category: Networking and Firewall
- URL: Github
Description¶
Security Groups should not have ports open in (20, 21, 22, 23, 115, 137, 138, 139, 2049, 3389)
Documentation
Code samples¶
Code samples with security vulnerabilities¶
Postitive test num. 1 - yaml file
Resources:
Ec2Instance:
Type: 'AWS::EC2::Instance'
Properties:
SecurityGroups:
- !Ref InstanceSecurityGroup
KeyName: mykey
ImageId: ''
InstanceSecurityGroup:
Type: AWS::EC2::SecurityGroup
Properties:
GroupDescription: Allow http to client host
VpcId:
Ref: myVPC
SecurityGroupIngress:
- IpProtocol: tcp
FromPort: 20
ToPort: 20
CidrIp: 0.0.0.0/0
SecurityGroupEgress:
- IpProtocol: tcp
FromPort: 80
ToPort: 80
CidrIp: 0.0.0.0/0
Postitive test num. 2 - json file
{
"Resources": {
"Ec2Instance": {
"Type": "AWS::EC2::Instance",
"Properties": {
"ImageId": "",
"SecurityGroups": [
"InstanceSecurityGroup"
],
"KeyName": "mykey"
}
},
"InstanceSecurityGroup": {
"Type": "AWS::EC2::SecurityGroup",
"Properties": {
"VpcId": {
"Ref": "myVPC"
},
"SecurityGroupIngress": [
{
"CidrIp": "0.0.0.0/0",
"IpProtocol": "tcp",
"FromPort": 20,
"ToPort": 20
}
],
"SecurityGroupEgress": [
{
"IpProtocol": "tcp",
"FromPort": 80,
"ToPort": 80,
"CidrIp": "0.0.0.0/0"
}
],
"GroupDescription": "Allow http to client host"
}
}
}
}
Code samples without security vulnerabilities¶
Negative test num. 1 - yaml file
Resources:
Ec2Instance:
Type: 'AWS::EC2::Instance'
Properties:
SecurityGroups:
- !Ref InstanceSecurityGroup
KeyName: mykey
ImageId: ''
InstanceSecurityGroup:
Type: AWS::EC2::SecurityGroup
Properties:
GroupDescription: Allow http to client host
VpcId:
Ref: myVPC
SecurityGroupIngress:
- IpProtocol: tcp
FromPort: 80
ToPort: 80
CidrIp: 127.0.0.1/32
SecurityGroupEgress:
- IpProtocol: tcp
FromPort: 80
ToPort: 80
CidrIp: 127.0.0.1/33
Negative test num. 2 - json file
{
"Resources": {
"Ec2Instance": {
"Type": "AWS::EC2::Instance",
"Properties": {
"SecurityGroups": [
"InstanceSecurityGroup"
],
"KeyName": "mykey",
"ImageId": ""
}
},
"InstanceSecurityGroup": {
"Properties": {
"VpcId": {
"Ref": "myVPC"
},
"SecurityGroupIngress": [
{
"IpProtocol": "tcp",
"FromPort": 80,
"ToPort": 80,
"CidrIp": "127.0.0.1/32"
}
],
"SecurityGroupEgress": [
{
"CidrIp": "127.0.0.1/33",
"IpProtocol": "tcp",
"FromPort": 80,
"ToPort": 80
}
],
"GroupDescription": "Allow http to client host"
},
"Type": "AWS::EC2::SecurityGroup"
}
}
}