Azure Virtual Network
      Back to home
      1. CNS Policies
      2. Azure Knowledge Base
      3. Azure Virtual Network

      Single Subnet

      Risk Level: Low

      Description: 

      This plugin guarantees that Virtual Networks have several networks in order to give a tiered design. In the case of a compromise, a single network within a Virtual Network raises the likelihood of a larger bomb radius. In a virtual network, a subnet is a set of IP addresses. For organization and security, a virtual network might be divided into many subnets.

      SentinelOne CNS strongly recommends creating multiple networks/subnets in each Virtual Network and changing the architecture to take advantage of public and private tiers.

      About the Service :

      The Azure Virtual Network (VNet) is the most basic component of your Azure private network. Many types of Azure resources, such as Azure Virtual Machines (VM), can connect securely with one other, the internet, and on-premises networks, thanks to VNet. Azure resources can securely connect with one other, the internet, and on-premises networks thanks to the Azure virtual network.

      Impact : 

      The risk of a broader blast radius in the event of a compromise can be increased by a single network within a Virtual Network. Multiple networks/subnets in each Virtual Network can take advantage of public and private tiers.

      Steps to Reproduce :

      1. Sign in to your Azure portal with your Azure account.
        https://portal.azure.com/#home 
      2. Navigate to Azure’s All Resources.
      3. In the Type filter select the value as Virtual Network and click Apply.
      4. Next, select the virtual network that you want to examine.
      5. Click on Subnets under Settings.
      6. Check if there are more than one subnets or not.
      7. Repeat the same steps for other virtual networks as well.

      Steps for Remediation :

      1. Sign in to your Azure portal with your Azure account.
        https://portal.azure.com/#home 
      2. Navigate to Azure’s All Resources.
      3. In the Type filter select the value as Virtual Network and click Apply.
      4. Next, select the virtual network that you want to examine.
      5. Click on Subnets under Settings.
      6. Check if there are more than one subnets or not.
      7. Click on +Subnet and then add the name of the subnet on the Add Subnet page, enter the required information and click on Save.
      8. Repeat the same steps for other virtual networks as well.

      References :