[Solved] The Remote Desktop Services Vulnerability CVE-2019-0708
Understanding CVE-2019-0708: The Remote Desktop Services Vulnerability
CVE-2019-0708, also known as “BlueKeep,” is a critical remote code execution vulnerability that affects Microsoft’s Remote Desktop Protocol (RDP) implementation. This vulnerability allows an unauthenticated attacker to connect to a vulnerable system using RDP and send specially crafted requests, leading to remote code execution2. The potential impact of this vulnerability is significant, as it could allow attackers to gain full control of the affected system.
Operating Systems Affected
CVE-2019-0708 affects several versions of Microsoft Windows, including both 32-bit and 64-bit versions. The following operating systems are vulnerable:
Windows 2000
Windows XP
Windows Vista
Windows 7
Windows Server 2003
Windows Server 2003 R2
Windows Server 2008
Windows Server 2008 R2
How to Fix the Vulnerability
To protect your systems from CVE-2019-0708, it is crucial to apply the necessary security updates provided by Microsoft. Here are the steps to fix the vulnerability:
Apply Security Updates: Microsoft has released patches for the affected operating systems. Ensure that your systems are up-to-date with the latest security updates4. You can download the patches from the Microsoft Update Catalog.
Enable Network Level Authentication (NLA): Enabling NLA can help mitigate the vulnerability. NLA requires authentication before establishing a remote desktop session, making it more difficult for attackers to exploit the vulnerability4.
Disable Remote Desktop Services: If Remote Desktop Services are not required, consider disabling them to reduce the attack surface.
Block RDP Port: Block port 3389 (the default port for RDP) using a network firewall or the Windows firewall. This can prevent remote attackers from accessing the RDP service1.
Creating the Registry Key
To enable Network Level Authentication (NLA) for RDP connections, you need to create a registry key. Follow these steps:
Open Registry Editor: Press Win + R, type regedit, and press Enter.
- Navigate to the Registry Path: Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\WinStations\RDP-Tcp.
2. Create a New DWORD Value: Right-click on the RDP-Tcp folder, select New, and choose DWORD (32-bit) Value.
3. Name the Value: Name the new DWORD value SecurityLayer.
4. Set the Value: Double-click on the SecurityLayer value and set its value to 2. This enables NLA for RDP connections1.
PowerShell Script
Here’s a PowerShell script to automate the process of enabling NLA for RDP connections:
powershell
# PowerShell script to enable Network Level Authentication (NLA) for RDP connections
# Define the registry path
$registryPath = “HKLM:\SYSTEM\CurrentControlSet\Control\Terminal Server\WinStations\RDP-Tcp”
# Create the SecurityLayer DWORD value and set its value to 2
New-ItemProperty -Path $registryPath -Name “SecurityLayer” -Value 2 -PropertyType DWORD -Force
# Output confirmation message
Write-Output “Network Level Authentication (NLA) for RDP connections has been enabled.”
Conclusion
CVE-2019-0708 is a critical vulnerability that requires immediate attention. By applying the necessary security updates, enabling NLA, and blocking RDP port 3389, you can significantly reduce the risk of exploitation1. Always ensure that your systems are up-to-date with the latest security patches to protect against potential threats.