Network Security Group With Unrestricted Access To SSH

• Query id: 2ade1579-4b2c-4590-bebb-f99bf597f612
• Query name: Network Security Group With Unrestricted Access To SSH
• Platform: AzureResourceManager
• Severity: Medium
• Category: Networking and Firewall
• URL: Github

Description

Port 22 (SSH) is exposed to the Internet
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - json file

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "2.0.0.0",
  "apiProfile": "2019-03-01-hybrid",
  "parameters": {},
  "variables": {},
  "functions": [],
  "resources": [
    {
      "name": "security group",
      "type": "Microsoft.Network/networkSecurityGroups",
      "apiVersion": "2020-11-01",
      "location": "location1",
      "tags": {},
      "properties": {
        "securityRules": [
          {
            "id": "id",
            "properties": {
              "description": "access to SSH",
              "protocol": "Tcp",
              "sourcePortRange": "*",
              "destinationPortRange": "22",
              "sourceAddressPrefix": "*",
              "destinationAddressPrefix": "*",
              "access": "Allow",
              "priority": 301,
              "direction": "Inbound"
            },
            "name": "security rule"
          },
           {
            "id": "id2",
            "properties": {
              "description": "access to RDP",
              "protocol": "Tcp",
              "sourcePortRange": "*",
              "destinationPortRange": "3389",
              "sourceAddressPrefix": "*",
              "destinationAddressPrefix": "*",
              "access": "Deny",
              "priority": 301,
              "direction": "Inbound"
            },
            "name": "security rule2"
          }
        ]
      },
      "resources": []
    }
  ],
  "outputs": {}
}

Positive test num. 2 - json file

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "2.0.0.0",
  "apiProfile": "2019-03-01-hybrid",
  "parameters": {},
  "variables": {},
  "functions": [],
  "resources": [
    {
      "name": "sample/securitygroup",
      "type": "Microsoft.Network/networkSecurityGroups/securityRules",
      "apiVersion": "2020-11-01",
      "properties": {
        "description": "access to SSH",
        "protocol": "Tcp",
        "sourcePortRange": "*",
        "destinationPortRanges": [
          "22-23"
        ],
        "sourceAddressPrefix": "*",
        "destinationAddressPrefix": "*",
        "access": "Allow",
        "priority": 100,
        "direction": "Inbound"
      }
    }
  ],
  "outputs": {}
}

Positive test num. 3 - json file

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "2.0.0.0",
  "apiProfile": "2019-03-01-hybrid",
  "parameters": {},
  "variables": {},
  "functions": [],
  "resources": [
    {
      "name": "securitygroup",
      "type": "Microsoft.Network/networkSecurityGroups",
      "apiVersion": "2020-11-01",
      "location": "location1",
      "tags": {},
      "properties": {},
      "resources": [
        {
          "type": "securityRules",
          "apiVersion": "2020-11-01",
          "properties": {
            "description": "access to SSH",
            "protocol": "Tcp",
            "sourcePortRange": "*",
            "destinationPortRanges": [
              "22-23"
            ],
            "sourceAddressPrefix": "*",
            "destinationAddressPrefix": "*",
            "access": "Allow",
            "priority": 100,
            "direction": "Inbound"
          },
          "name": "sr"
        }

      ]
    }
  ],
  "outputs": {}
}

Positive test num. 4 - json file

{
  "properties": {
    "template": {
      "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
      "contentVersion": "2.0.0.0",
      "apiProfile": "2019-03-01-hybrid",
      "parameters": {},
      "variables": {},
      "functions": [],
      "resources": [
        {
          "name": "security group",
          "type": "Microsoft.Network/networkSecurityGroups",
          "apiVersion": "2020-11-01",
          "location": "location1",
          "tags": {},
          "properties": {
            "securityRules": [
              {
                "id": "id",
                "properties": {
                  "description": "access to SSH",
                  "protocol": "Tcp",
                  "sourcePortRange": "*",
                  "destinationPortRange": "22",
                  "sourceAddressPrefix": "*",
                  "destinationAddressPrefix": "*",
                  "access": "Allow",
                  "priority": 301,
                  "direction": "Inbound"
                },
                "name": "security rule"
              }
            ]
          },
          "resources": []
        }
      ],
      "outputs": {}
    },
    "parameters": {}
  },
  "kind": "template",
  "type": "Microsoft.Blueprint/blueprints/artifacts",
  "name": "myTemplate"
}

Positive test num. 5 - json file

{
  "properties": {
    "template": {
      "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
      "contentVersion": "2.0.0.0",
      "apiProfile": "2019-03-01-hybrid",
      "parameters": {},
      "variables": {},
      "functions": [],
      "resources": [
        {
          "name": "sample/securitygroup",
          "type": "Microsoft.Network/networkSecurityGroups/securityRules",
          "apiVersion": "2020-11-01",
          "properties": {
            "description": "access to SSH",
            "protocol": "Tcp",
            "sourcePortRange": "*",
            "destinationPortRanges": [
              "22-23"
            ],
            "sourceAddressPrefix": "*",
            "destinationAddressPrefix": "*",
            "access": "Allow",
            "priority": 100,
            "direction": "Inbound"
          }
        }
      ],
      "outputs": {}
    },
    "parameters": {}
  },
  "kind": "template",
  "type": "Microsoft.Blueprint/blueprints/artifacts",
  "name": "myTemplate"
}

Positive test num. 6 - json file

{
  "properties": {
    "template": {
      "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
      "contentVersion": "2.0.0.0",
      "apiProfile": "2019-03-01-hybrid",
      "parameters": {},
      "variables": {},
      "functions": [],
      "resources": [
        {
          "name": "securitygroup",
          "type": "Microsoft.Network/networkSecurityGroups",
          "apiVersion": "2020-11-01",
          "location": "location1",
          "tags": {},
          "properties": {},
          "resources": [
            {
              "type": "securityRules",
              "apiVersion": "2020-11-01",
              "properties": {
                "description": "access to SSH",
                "protocol": "Tcp",
                "sourcePortRange": "*",
                "destinationPortRanges": [
                  "22-23"
                ],
                "sourceAddressPrefix": "*",
                "destinationAddressPrefix": "*",
                "access": "Allow",
                "priority": 100,
                "direction": "Inbound"
              },
              "name": "sr"
            }

          ]
        }
      ],
      "outputs": {}
    },
    "parameters": {}
  },
  "kind": "template",
  "type": "Microsoft.Blueprint/blueprints/artifacts",
  "name": "myTemplate"
}

Code samples without security vulnerabilities

Negative test num. 1 - json file

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "2.0.0.0",
  "apiProfile": "2019-03-01-hybrid",
  "parameters": {},
  "variables": {},
  "functions": [],
  "resources": [
    {
      "name": "security group",
      "type": "Microsoft.Network/networkSecurityGroups",
      "apiVersion": "2020-11-01",
      "location": "location1",
      "tags": {},
      "properties": {
        "securityRules": [
          {
            "id": "id",
            "properties": {
              "description": "access to SSH",
              "protocol": "Tcp",
              "sourcePortRange": "*",
              "destinationPortRange": "22",
              "sourceAddressPrefix": "*",
              "destinationAddressPrefix": "*",
              "access": "Deny",
              "priority": 301,
              "direction": "Inbound"
            },
            "name": "security rule"
          }
        ]
      },
      "resources": []
    }
  ],
  "outputs": {}
}

Negative test num. 2 - json file

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "2.0.0.0",
  "apiProfile": "2019-03-01-hybrid",
  "parameters": {},
  "variables": {},
  "functions": [],
  "resources": [
    {
      "name": "sample/securitygroup",
      "type": "Microsoft.Network/networkSecurityGroups/securityRules",
      "apiVersion": "2020-11-01",
      "properties": {
        "description": "access",
        "protocol": "Tcp",
        "sourcePortRange": "*",
        "destinationPortRanges": [
          "4030-5100"
        ],
        "sourceAddressPrefix": "*",
        "destinationAddressPrefix": "*",
        "access": "Allow",
        "priority": 100,
        "direction": "Inbound"
      }
    }
  ],
  "outputs": {}
}

Negative test num. 3 - json file

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "2.0.0.0",
  "apiProfile": "2019-03-01-hybrid",
  "parameters": {},
  "variables": {},
  "functions": [],
  "resources": [
    {
      "name": "securitygroup",
      "type": "Microsoft.Network/networkSecurityGroups",
      "apiVersion": "2020-11-01",
      "location": "location1",
      "tags": {},
      "properties": {},
      "resources": [
        {
          "type": "securityRules",
          "apiVersion": "2020-11-01",
          "properties": {
            "description": "access",
            "protocol": "Tcp",
            "sourcePortRange": "*",
            "destinationPortRanges": [
              "6634"
            ],
            "sourceAddressPrefix": "*",
            "destinationAddressPrefix": "*",
            "access": "Allow",
            "priority": 100,
            "direction": "Inbound"
          },
          "name": "sr"
        }

      ]
    }
  ],
  "outputs": {}
}

Negative test num. 4 - json file

{
  "properties": {
    "template": {
      "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
      "contentVersion": "2.0.0.0",
      "apiProfile": "2019-03-01-hybrid",
      "parameters": {},
      "variables": {},
      "functions": [],
      "resources": [
        {
          "name": "security group",
          "type": "Microsoft.Network/networkSecurityGroups",
          "apiVersion": "2020-11-01",
          "location": "location1",
          "tags": {},
          "properties": {
            "securityRules": [
              {
                "id": "id",
                "properties": {
                  "description": "access to SSH",
                  "protocol": "Tcp",
                  "sourcePortRange": "*",
                  "destinationPortRange": "22",
                  "sourceAddressPrefix": "*",
                  "destinationAddressPrefix": "*",
                  "access": "Deny",
                  "priority": 301,
                  "direction": "Inbound"
                },
                "name": "security rule"
              }
            ]
          },
          "resources": []
        }
      ],
      "outputs": {}
    },
    "parameters": {}
  },
  "kind": "template",
  "type": "Microsoft.Blueprint/blueprints/artifacts",
  "name": "myTemplate"
}

Negative test num. 5 - json file

{
  "properties": {
    "template": {
      "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
      "contentVersion": "2.0.0.0",
      "apiProfile": "2019-03-01-hybrid",
      "parameters": {},
      "variables": {},
      "functions": [],
      "resources": [
        {
          "name": "sample/securitygroup",
          "type": "Microsoft.Network/networkSecurityGroups/securityRules",
          "apiVersion": "2020-11-01",
          "properties": {
            "description": "access",
            "protocol": "Tcp",
            "sourcePortRange": "*",
            "destinationPortRanges": [
              "4030-5100"
            ],
            "sourceAddressPrefix": "*",
            "destinationAddressPrefix": "*",
            "access": "Allow",
            "priority": 100,
            "direction": "Inbound"
          }
        }
      ],
      "outputs": {}
    },
    "parameters": {}
  },
  "kind": "template",
  "type": "Microsoft.Blueprint/blueprints/artifacts",
  "name": "myTemplate"
}

Negative test num. 6 - json file

{
  "properties": {
    "template": {
      "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
      "contentVersion": "2.0.0.0",
      "apiProfile": "2019-03-01-hybrid",
      "parameters": {},
      "variables": {},
      "functions": [],
      "resources": [
        {
          "name": "securitygroup",
          "type": "Microsoft.Network/networkSecurityGroups",
          "apiVersion": "2020-11-01",
          "location": "location1",
          "tags": {},
          "properties": {},
          "resources": [
            {
              "type": "securityRules",
              "apiVersion": "2020-11-01",
              "properties": {
                "description": "access",
                "protocol": "Tcp",
                "sourcePortRange": "*",
                "destinationPortRanges": [
                  "6634"
                ],
                "sourceAddressPrefix": "*",
                "destinationAddressPrefix": "*",
                "access": "Allow",
                "priority": 100,
                "direction": "Inbound"
              },
              "name": "sr"
            }

          ]
        }
      ],
      "outputs": {}
    },
    "parameters": {}
  },
  "kind": "template",
  "type": "Microsoft.Blueprint/blueprints/artifacts",
  "name": "myTemplate"
}