How to: Increase Cloud Security with new Azure JIT VM Access

Every day, new security solutions are coming into the Azure security Center, such as JIT VM Access, and these innovations further tighten the security layer. We will keep you updated!

Experts have been observing that hackers seem to be targeting the Brute Force or Port Scanning on management ports, such as RDP and SSH, which are often left open for administrators to access systems in their cloud environments. Microsoft Azure has released a new feature to prevent just that.

With the new Just in Time Virtual Machine (JIT VM) Access mechanism, announced in April 2018, the Microsoft Azure Security Center now helps clients detect and get notified of attacks such as the ones mentioned above. This new layer of security, which provides you with controlled access to VMs at any time, can significantly reduce this kind of attack exposure by allowing you to deny persistent access.

According to the security policy you set up, Azure Security Center can enable just-in-time (JIT) access on your existing VMs as well as on your newly created VMs. When JIT VM access is enabled, Azure security Center closes traffic to the ports defined by creating the Network security Group rules. If necessary, you can request to open the required port for the approved period of time for the IP addresses approved for the VM and only for users with the appropriate permissions. Requests are saved in the Azure Activity Log, so you can easily monitor and control access. You can also enable JIT VM access, configure them with policy, and request access through PowerShell cmdlets. These new features are available within the Azure Security Center standard pricing tier and are free during the first 60 days.

I signed in to the Azure portal on my own account, clicked on the Security Center and then clicked on JIT VM Access.

To get free access for the first 60 days, press the "Apply Standard Plan" button.

If you have an existing OMS workspace, you can use it to store these logs. As I didn't have one yet, I created a new workspace.

To create a new workspace, enter your OMS workspace name, select your subscription, create a new resource group or select the existing one, then press the “OK” button to complete the creation process.

Our OMS Workspace is ready to record all JIT VM Access activities in the log.

The JIT VM Access is now ready to use. Now I can select the machine or machines I want to activate for JIT VM access and then press the “Enable JIT” button.

I can configure JIT VM Access now and define permissions and times for ports. I select the VM for this and press the “Edit” button.

I use this section to open the port, to define the source IP that is allowed access. Again, I can set the time range for access in this section.

Now, I enter my own real IP in 3389 RDP port and allow access for one hour.

Here are the activity logs for the machine that has JIT VM Access enabled.

I can see the source IP address and destination IP address of the machine in the activity logs. It is also possible to see the rules’ name and port information in this section.