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How to protect RDP your connections to your server?

This article provides you with steps to secure RDP connections to your server.

 

 

Rename the standard administrator account

 

  • Press Win + X and select “Computer management”:

 

RDP-protection-- computer management.png
  • Then select “Local users” –→ “Users” –→ click with the right mouse button on user’s name “Administrator” and select

 

RDP-protection-- rename administrator_0.png

 

  • Rename the Administrator user and use this name for subsequent connection to the remote desktop.

Blocking of RDP connections for accounts with an empty password

 

Security can be improved by prohibiting to connect to accounts with empty passwords. To do this, you should enable security policy “Accounts”: permit to use empty passwords only for log-in from the console”:

  • Open local security policy (press Win + R and enter command secpol.msc)
  • Browse to “Local policies” –-> “Security parameters”.

 

RDP-protection-- security param.png
  • Double click on policy “Accounts: permit to use empty passwords…» and make sure that it is enabled:

 

RDP-protection-- limit of blank password.png

 

 


Change of standard port Remote Desktop Protocol

 

It’s good practice to change a standard port, on which RDP protocol works. The method to this is described in our instruction: Windows Server 2012.

Protection from brute force

 

In order to block multiple attempts to connect using the wrong data, it is possible to trace the event log and manually block attacking IP addresses using Windows firewall or a ready application. Let’s review the last case in detail.


We will use free SW for blocking of attacking IP addresses – IPBan. This application is verified and operates with Windows Server 2008 all subsequent versions. Windows XP and Server 2003 are not supported. Its operation algorithm is simple: the program monitors Windows event log, record log-in attempts and blocks IP address for 24 hours after 5 attempts of the hacker.

  •  Download an archive with the program here;
  •  It contains two archives IPBan-Linux-x64.zip and IPBan-Windows-x86.zip, we need the last one. Unpack the IPBan-Windows-x86.zip archive into any convenient place (for example, into C: drive root directory);

 

  • As files, downloaded from the Internet, are automatically blocked by the system for security. All files should be unblocked for the application operation. Click with the right mouse button on all extracted files and select properties.
  • Necessarily select “unblock”, if this parameter is available. Or open the PowerShell window (Win + R, enter PowerShell and click on “ОК”) and enter the following command:
get-childitem “folder location” | unblock-file -confirm

For example:

RDP-protection-- powershell - unblock_0.png

 

  • You should make the following changes in the local security policy, in order to make sure that IP addresses are displayed in system logs. Open “Local security policy” (Win + R, enter secpol.msc and press “OK”). Browse to “Local policies” –> “Audit policy” and enable registration of failures for “Audit account logon events” and “Audit logon events”:

 

RDP-protection-- audit-on.png

 

 

RDP-protection-- audit-chekbox.png

 

  • For Windows Server 2008 or equivalent, you should disable NTLM logins and permit only NTLM2 log-in. There is no other method to obtain an IP address for log in NTLM in Windows Server 2008. Open “Local security policy” (Win + R, enter secpol.msc and press “OK”). Browse to “Local policies” –> “Security parameters” –> “Network security: NTLM restrictions: NTLM incoming traffic” and set a value “Prohibit all accounts”:

 

RDP-protection-- local security-NTLM.png
  • Now it is required to create IPBan service so that the application is launched after the system start-up and operates in the background. Launch PowerShell (Win + R, enter PowerShell and press “ОК”) and run the following command:
sc.exe create IPBAN type= own start= auto binPath= c:\"Directory with program"\IPBan.exe DisplayName= IPBAN

For example:

 

RDP-protection-- create service IPBan.png
  • Go to services (Win + R, enter services.msc and press “OK”) and launch IPBAN service. Hereafter, it will be launched automatically:
RDP-protection-- start ipban.png

 

  • In “Task dispatcher” you can look up if the service is launched and operates:

 

RDP-protection-- task manager.png
  • Thus, the program monitors failed authorization attempts and add unwanted IP address into the created rule for incoming connections of Windows firewall:
RDP-protection-- firewall rules.png
  • Blocked IP addresses can be unblocked manually. Go to “Scope” tab, located in “IPBan_0” rule properties and remove the required IP address the list:

 

RDP-protection-- remove IPs.png

 

 

 

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