Default Security Groups With Unrestricted Traffic

• Query id: 46883ce1-dc3e-4b17-9195-c6a601624c73
• Query name: Default Security Groups With Unrestricted Traffic
• Platform: Terraform
• Severity: High
• Category: Networking and Firewall
• CWE: 285
• URL: Github

Description

Check if default security group does not restrict all inbound and outbound traffic.
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - tf file

resource "aws_default_security_group" "positive1" {
  vpc_id = aws_vpc.mainvpc.id

  ingress {
    protocol  = -1
    self      = true
    from_port = 0
    to_port   = 0
    cidr_blocks = ["0.0.0.0/0"]
  }
}

resource "aws_default_security_group" "positive2" {
  vpc_id = aws_vpc.mainvpc.id

  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    ipv6_cidr_blocks = ["::/0"]
  }
}

resource "aws_default_security_group" "positive3" {
  vpc_id = aws_vpc.mainvpc.id

  ingress {
    protocol  = -1
    self      = true
    from_port = 0
    to_port   = 0
    cidr_blocks = ["0.0.0.0/0"]
  }

  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    ipv6_cidr_blocks = ["::/0"]
  }
}

Code samples without security vulnerabilities

Negative test num. 1 - tf file

resource "aws_default_security_group" "negative1" {
  vpc_id = aws_vpc.mainvpc.id

  ingress {
    protocol  = -1
    self      = true
    from_port = 0
    to_port   = 0
    cidr_blocks = ["10.1.0.0/16"]
    ipv6_cidr_blocks = ["250.250.250.1:8451"]
  }

  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = ["10.1.0.0/16"]
    ipv6_cidr_blocks = ["250.250.250.1:8451"]
  }
}