To minimize the impact of a ransomware attack, it is critical to detect and mitigate the infection as early as possible. Still, traditional signature-based firewalls and antivirus software may not be able to detect novel malware (new viruses that haven’t been seen before) and zero-day exploits that hackers frequently use to deploy ransomware on a network. For example, in early 2021, Microsoft detected multiple zero-day exploits that hackers used to attack on-premises Exchange servers. That is why it is essential to have a comprehensive network monitoring solution for preventing, detecting, and removing ransomware on a network. However, it’s essential to understand what ransomware is and how it works before diving into the best strategies for detecting ransomware on a network.
What is ransomware, and how does it work?
Ransomware is malware (malicious software) that takes systems or data hostage until you pay a ransom to the hacker. Usually, hackers will encrypt your files, and after you pay the ransom, they’ll provide an encryption key. On some occasions, the hacker will just take your money and run; other times, they’ll decrypt your files but leave malware on your system so they can attack in the future.
Even in the best-case scenario, where access to your files is fully restored, and the malware is completely removed, you’re likely to face significant business interruptions both during and after the breach. One notable example would be Colonial Pipeline, which faced a ransomware attack in May of 2021. Even after paying the ransom, they had to shut down operations for several days while removing all traces of malware from their network, causing President Biden to declare a state of emergency.
So, not only do you pay a steep cost for the ransom, but you’ll also pay the cost of lost business, lost consumer trust, and even potential legal fines if regulated data was exposed during the attack.
Detecting ransomware on a network
Detecting ransomware on a network is notoriously difficult until it has fully infected the network and activated its encryption. That’s because traditional security solutions rely on signature-based detection, which means they keep a database of known virus types to compare potential infections. If a piece of malware doesn’t match anything in the signature database, or if that database isn’t kept up-to-date, it could get through firewall and antivirus software.
Since ransomware attacks frequently use novel malware, you may need to instead look for signs of that infection interacting with systems and files on your network. This requires a comprehensive network that gives complete visibility on enterprise infrastructure, including edge networks and remote and branch locations. For example, a SIEM (security information and event management) solution offers a holistic view of your network by collecting logs and event data from all your systems and applications.
Collecting data is only the first step—you also need to know what to look for. Here are some of the signs of a ransomware infection that you can detect through network monitoring:
- New processes and code. Any unfamiliar processes and programs launching on your systems could be a sign of ransomware taking hold.
- Registry changes. Unexpected changes to the Windows registry on servers and other devices are also early warning signs of ransomware.
- Unusual internal and external traffic. Traffic to and from an unknown external source could be a sign of hackers controlling their ransomware or exfiltrating data. Unusual traffic between systems on your network that don’t usually communicate could be a sign of ransomware spreading between devices.
- Elevated PowerShell scripts. Hackers frequently use elevated PowerShell scripts to propagate ransomware throughout a network.
- Unexpected file modifications. Ransomware typically works by encrypting your files so that anomalous file modification activity could be a late-stage sign of a ransomware infection.
- Data exfiltration. Hackers can remove valuable data from your network to use in their ransom requests. If you notice any large-scale data transfers of your network, it’s another late-stage warning of a ransomware attack.
If you catch a ransomware infection on your network before it has encrypted any of your files, then you may be able to remove it the same way you’d remove other kinds of malware. You should isolate infected devices, run malware removal programs, and thoroughly scrub for any lingering trace of ransomware. It may be necessary to reinstall the operating system from scratch to clean the system entirely.
However, if the ransomware infection has begun encrypting files already, none of these removal methods will reverse that process or restore access to your files. That’s why it’s so essential to prevent a ransomware infection in the first place.
Three critical steps to ensure network security against ransomware
Though there aren’t any security solutions or strategies that provide 100% protection against malware, there are still some best practices to follow to decrease the risk of infection:
1. Simplify your security and infrastructure management.
Often, large enterprises end up with a patchwork of security solutions and infrastructure configurations spread out across many geographic locations and cloud providers. Maintaining security standards, patch management schedules, and monitoring dashboards across many different platforms increases the chances of mistakes leading to a ransomware attack. That’s why you should look for opportunities to consolidate your security and infrastructure management to reduce the number of physical devices you’re responsible for configuring and securing. You should also avoid vendor lock-in by choosing a vendor-neutral infrastructure management solution, so your security teams can provide the best possible care and attention across your entire enterprise network from one unified control panel.
2. Establish a robust and secure backup strategy.
You need to backup all your critical data systems and fully secure backups. Backups need to be isolated from the enterprise network so ransomware can’t access them from any other infected systems. It is also important to test backups frequently and ensure teams know how to execute disaster recovery plans. If a solid backup and recovery strategy is in place, many of the expenses involved in a ransomware attack may be avoided.
3. Create a culture of security.
Hackers frequently use social engineering tactics (such as phishing) to get their ransomware onto a network. Educating staff on recognizing social engineering attempts, avoiding clicking on suspicious links, and reporting potential security incidents to IT can go a long way towards preventing a ransomware infection. Every member of an organization should feel responsible for enterprise network security and know how to spot and respond to a potential infection.
Detect and prevent ransomware attacks with the right solutions
Ransomware is a major threat to enterprise network security, but you can detect or even prevent an attack with the right tools and plans in place. By utilizing SIEM or other comprehensive network monitoring solutions, you can spot the signs of ransomware moving throughout your network.
Even better, you can prevent a ransomware attack from occurring at all by implementing a robust backup strategy, educating staff at every level of your organization, and consolidating your security and infrastructure management tools with a solution like Nodegrid. ZPE Systems’ Nodegrid simplifies network management by reducing remote and edge infrastructure into one centralized control panel.