The last few years have seen a surge of breaches ranging from credential stuffing to brute force attacks. Analyzing the breaches generally points back to a breakdown in IT fundamental practices. Time and again hackers have proven that they just have to be right once, while IT and cybersecurity professionals have to get it right every time. Getting it right also means not losing perspective of basic IT fundamentals - cutting corners can have devastating effects, as so many local and state governments can attest, alongside businesses.
DHS and the FBI recently addressed mitigation recommendations in dealing with SamSam Ransomware. Every single recommendation is wrapped around basic fundamental practices in information technology and not just best practice. As IT professionals, we have to embrace these and some common sense!
Here are the points from DHS and FBI:
System owners and administrators should review any configuration changes before implementation to avoid unwanted impacts.
Audit your network for systems that use RDP for remote communication. Disable the service if unneeded or install available patches. Users may need to work with their technology venders to confirm that patches will not affect system processes.
Verify that all cloud-based virtual machine instances with public IPs have no open RDP ports, especially port 3389, unless there is a valid business reason to keep open RDP ports. Place any system with an open RDP port behind a firewall and require users to use a virtual private network (VPN) to access that system.
Enable strong passwords and account lockout policies to defend against brute force attacks.
Where possible, apply two-factor authentication.
Regularly apply system and software updates.
Maintain a good back-up strategy.
Enable logging and ensure that logging mechanisms capture RDP logins. Keep logs for a minimum of 90 days and review them regularly to detect intrusion attempts.
When creating cloud-based virtual machines, adhere to the cloud provider’s best practices for remote access.
Ensure that third parties that require RDP access follow internal policies on remote access.
Minimize network exposure for all control system devices. Where possible, disable RDP on critical devices.
Regulate and limit external-to-internal RDP connections. When external access to internal resources is required, use secure methods such as VPNs. Of course, VPNs are only as secure as the connected devices.
Restrict users' ability (permissions) to install and run unwanted software applications.
Scan for and remove suspicious email attachments; ensure the scanned attachment is its "true file type" (i.e., the extension matches the file header).
Disable file and printer sharing services. If these services are required, use strong passwords or Active Directory authentication.