What is RDP?
Remote Desktop Protocol (RDP) is a software standard developed by Microsoft that allows users to connect to and use another computer remotely. RDP has several capabilities that make it popular among users, including:
Core functionality: RDP works across various operating systems, including Windows, Linux, macOS, iOS, and Android, allowing users to connect remotely to diverse systems.
Protocol features: Beyond basic screen sharing and secure file transfer, RDP has functionalities like image and video transmission and bi-directional audio streaming, which are helpful for virtual meetings and multimedia applications.
Default port: RDP primarily operates on TCP port 3389, which can pose security risks as attackers often target it.
Authentication methods: RDP supports multiple authentication methods, including traditional username/password combinations and biometric options through Windows Hello, which enables secure logins with facial recognition or fingerprint scans.
Encryption: The protocol uses built-in standard encryption for secure data transmission, protecting information shared over RDP.
Use cases: RDP is commonly used for remote work, IT/ technical support, and server management.
Common RDP security risks
Though Remote Desktop Protocols (RDPs) are generally robust, they have exploitable weaknesses when poorly protected. Understanding how these vulnerabilities could be used to breach your connections is essential because it helps you decide on the best approach to secure your data.
Common security risks that are associated with RDPs include:
Brute force attacks: These use automated tools to make repeated guesses of login credentials until successful entry is achieved. This method is especially effective against systems with weak passwords and inadequate lockout policies.
Credential theft: Some attackers deploy man-in-the-middle tactics to steal login data during authentication. They then use the stolen credentials to access the system.
BlueKeep and related vulnerabilities: Older operating systems, including outdated versions of Microsoft Windows, often contain security vulnerabilities like BlueKeep. These weaknesses can allow attackers to execute code remotely without user authentication by exploiting RDPs.
Denial of Service (DoS) attacks: By overwhelming RDP servers with connection requests, DoS attacks can temporarily shut down access for legitimate users, resulting in downtime and productivity losses. These attacks can be incredibly costly for organizations that rely heavily on RDP for remote work and server management.
Insider threats: While often overlooked, insider threats are growing, especially in hybrid work environments where remote access is shared. Authorized users with malicious intent can exfiltrate sensitive data or intentionally disrupt operations, posing a severe risk to business continuity.
Exposed RDP port: TCP port 3389, the standard RDP port, is highly susceptible to scanning and brute-force attacks if left open to the internet. Exposing this port can provide attackers with a direct route to company servers, increasing the chance of unauthorized access.
9 Ways to Mitigate RDP Security Risks
Understanding the risks associated with RDP is only the first step—effectively reducing these risks requires a comprehensive approach to security. No single measure can fully protect your network, so it's crucial to adopt multiple layers of defense to strengthen RDP connections against potential attacks.
Some robust strategies that reduce remote desktop vulnerability include:
1. Implement strong authentication
Consider implementing multifactor authentication (MFA) by requiring users to provide something they know (like a password) along with something they have (like a code from an authenticator app) to log in. Mandate using long and complex passwords (at least 8 characters) and include upper and lowercase letters, numbers, and symbols.
2. Network Level Authentication (NLA)
Enable a Network Level Authentication (NLA) for your system to check user credentials before establishing an entire RDP session. Hence, attackers can't exploit the RDP service itself to get in.
3. Restrict RDP access
Be selective regarding who you allow RDP access to. Set up firewall rules that block RDP from public IP addresses on the internet, only allowing connections from specific internal or VPN ranges you designate.
You can also segment parts of your network to restrict which systems can communicate via RDP based on their Mac Address or specified protocols. Limiting the attack surface makes unauthorized RDP connections much less likely.
4. Regular patching
Cybercriminals are constantly probing for new vulnerabilities, so updating your software with the most current security fixes should be a top priority.
5. Monitoring and logging
Implement detailed logging and real-time monitoring of all RDP sessions to detect suspicious activities like repeated failed attempts or logins from unusual locations or times. Catching and investigating red flags early allows you to secure RDP before incidents escalate into breaches.
6. Limit user privileges
When configuring RDP access, user accounts should only be permitted the minimum privileges needed to do their jobs. Limiting privileges contains the damage if a profile is compromised, preventing lateral movement across your network.
7. Change default ports
Cybercriminals frequently scan for systems with RDP enabled on default port 3389. Changing to a non-standard high-number port makes it less likely for attackers to find and target your RDP service in automated scans.
8. Implement account lockout policies
Protect against brute force attacks by applying rate limiting that locks accounts out for at least 15 minutes after six failed attempts. This approach thwarts repeated rapid-fire login efforts while minimizing disruption for legitimate users mistyping passwords.
9. Use Remote Desktop Gateway
An RD Gateway server acts as an extra hop for RDP traffic, validating connections before they reach your network. Your users first connect to the Gateway, forwarding authorized sessions to their final destination. This strategy provides an additional layer of security and more granular access control to protect RDP connections better.
How Fastly enhances RDP security
RDPs are a valuable tool for remote access. Though generally safe, they remain vulnerable to critical security threats that require stringent measures to prevent unauthorized access and data breaches.
Implementing strong safeguards, such as multifactor authentication and access control, is essential for preventing costly breaches.
Fastly offers strong protection against common vulnerabilities, allowing you to boost your RDP security. The platform's robust security features significantly reduce weaknesses related to remote connections like RDP, which is often a target for brute force attacks, malware injections, and man-in-the-middle (MitM) threats.
Some key Fastly solutions that help to secure RDPs include:
Web Application Firewall (WAF): Fastly's Next-Gen WAF protects by blocking malicious traffic aimed at your RDP infrastructure.
DDoS protection: The DDoS mitigation services that Fastly offers ensure your RDP service remains in operation during volumetric attacks, maintaining continuous operation for remote workers.
Edge cloud security: Since Fastly processes connection requests closer to users, latency is low, and connections are encrypted, reducing the risk of man-in-the-middle attacks on remote sessions.
TLS encryption: When using Fastly, communication over public networks is encrypted using the latest TLS protocols, enhancing security for RDP connections.
Real-time monitoring and logging: Fastly provides real-time logging and monitoring, allowing you to track and deal with suspicious activity across various RDP sessions.
Zero trust architecture: The zero trust security frameworks integrated with Fastly ensure that only authorized users access RDP connections.
Request a free demo today to see how Fastly helps protect your access infrastructure.
