Ransomware is a form of malware that encrypts a victim’s files and demands payment in order to decrypt them. It has become an increasingly common and damaging form of cyber attack in recent years. When ransomware infects a system, it can bring operations to a halt by locking access to critical data and systems. With thousands of new ransomware variants appearing each year, organizations must make ransomware prevention a top priority. But where should they start? What is the very first step to stopping these attacks?
Know Your Enemy: Understand Ransomware Threats
The first step in ransomware defense is to understand the threat landscape. There are two main types of ransomware to be aware of:
Crypto-Ransomware
Crypto-ransomware is the most common variant. It uses strong encryption algorithms to lock files and demands ransom payment, usually in Bitcoin or other cryptocurrency, in order to receive the decryption key. Well-known examples include Ryuk, Conti and REvil. Crypto-ransomware typically spreads through phishing emails with malicious attachments or by exploiting security vulnerabilities.
Locker-Ransomware
Locker-ransomware does not encrypt files but instead locks users out of their systems or certain functions. It may change system passwords, lock screens, or disable certain programs or functionalities until ransom is paid. Locker-ransomware is less common than crypto-ransomware but can still cause significant disruption.
Understanding the different ransomware approaches, objectives, and typical distribution methods is step one towards better defense.
Start with Security Basics
With ransomware threats in mind, the next step is to lock down the security basics. Cybercriminals often gain initial access through common security gaps, so closing these off greatly reduces the attack surface. Important security hygiene practices include:
Keep Software Patched and Updated
Always apply the latest security updates for operating systems, applications, and network devices. Ransomware often exploits known software flaws, so patching is critical. Enable automatic updates wherever possible. Prioritize updates for internet-facing services or tools like PowerShell that are frequently targeted.
Secure Accounts with MFA
Enforce multifactor authentication (MFA) across all user and admin accounts. Compromised credentials are one of the top vectors for ransomware. MFA ensures accounts cannot be accessed based only on stolen passwords. Require strong, complex passwords as well.
Limit Access and Privileges
Use the principle of least privilege to restrict unnecessary access. Limit admin privileges and only give users the access they need to do their jobs. Segment networks to control lateral movement. Disable macros, PowerShell, and unnecessary features in tools like Microsoft Office.
Back Up Critical Data
Maintain current backups of irreplaceable data for recovery if ransomware strikes. Keep at least 3 copies on 2 different media with 1 offline. Test backups regularly for reliability.
These steps help “shrink” the attack surface and force ransomware to work much harder to penetrate defenses.
Deploy Multi-Layered Security
With strong security hygiene in place, the next priority is deploying layered security defenses designed to catch threats. Important technologies include:
Next-Gen Antivirus
Traditional antivirus is ineffective at catching new ransomware strains. Move to next-gen antivirus with advanced heuristics to detect and block ransomware execution. Enable runtime behavior monitoring to catch malicious activities like file encryption.
Email Security
Invest in dedicated email security to block malicious attachments, quarantine risky emails with links/macros, and filter obvious phishing attempts. This prevents infection at the email gateway.
Endpoint Detection & Response
Install EDR tools on endpoints and servers to monitor for ransomware indicators like suspicious registry changes, network connections to C2 servers, attempts to disable security tools, and more. EDR can halt ransomware mid-attack.
IPS and Firewalls
Network-based IPS and next-gen firewalls add another layer by scanning traffic and blocking known indicators of compromise associated with ransomware. This prevents call outs to command and control servers.
Layered security increases the chances of detecting and stopping ransomware at different stages of the attack chain.
Train Employees
Technology alone is not enough. Employees are a critical defense layer, as human-operated ransomware often starts with phishing or social engineering. Prioritize regular cybersecurity awareness training for all employees on topics like:
- Identifying suspicious emails and unsafe attachments
- Dangers of enabling macros in documents
- Spotting fake login pages for credential theft
- Reporting potential infections or issues urgently
Test employees with simulated phishing attacks to identify gaps and further educate users on real threats. Emphasized how one lapse in judgment can lead to ransomware impacting the entire organization. Ongoing user education develops an essential human immune system against cyberattacks.
Test Incident Response
Despite best efforts, ransomware may still penetrate defenses. Therefore, test incident response plans regularly to improve reaction time and recovery when an attack occurs. Key areas to review include:
- Ransomware detection and containment procedures
- Outbreak investigation and root cause analysis
- Using backups to restore encrypted or altered files
- Public relations and communications strategies
- Notifying customers, partners, and relevant authorities if needed
Practice these response steps like a fire drill to minimize business disruption during real ransomware incidents.
Consider Cyber Insurance
Cyber insurance provides another layer of protection against ransomware losses. Policies may cover costs of investigation, paying ransom demands, litigation expenses, and lost income during business disruption. Evaluate options but read policies closely, as coverage varies greatly by provider.
Prevent Ransomware Infection with a Vaccine
Vaccines work by exposing the body’s immune system to a weakened form of a virus, allowing it to develop antibodies and defense mechanisms. Similarly, one innovative method of “vaccinating” systems against ransomware is to expose them to non-harmful software mimicking ransomware behaviors.
Canary Files
Canary files are encrypted file folders placed as “bait”, which security software monitors for unauthorized changes. If ransomware is detected encrypting a canary folder, it triggers an immediate alert to isolate the threat. This detects and stops ransomware in action.
Ransomware Simulations
One can run non-malicious software internally that performs actions similar to ransomware code. This safely tests whether security controls detect and respond to ransomware-like activities without any actual damage. Running frequent simulations exposes systems to ransomware behaviors, triggering automatic improvements to defenses.
Ransomware vaccines help security tools and teams learn to recognize malicious activities faster. Like biological vaccines, they build up organizational immunity against infections.
Segment and Compartmentalize
Preventing ransomware comes down to denying it pathways to spread within systems. Network segmentation and compartmentalization help contain threats if one part of infrastructure is breached:
Network Segmentation
Divide networks into smaller segments using VLANs, subnets, or microsegmentation. Limit communication between segments to only what is required. This prevents lateral ransomware movement between different departments, branches or device types.
Compartmentalize Systems
Similarly, contain ransomware locally on endpoints by compartmentalizing and separating systems. On user devices, utilize containerization and sandboxes to isolate browsers, emails clients, and workflow applications from each other. Strictly limit their access to other parts of the system.
Like waterproof compartments in a ship, segmentation and compartmentalization prevent one ransomware breach from sinking the entire organization.
conclusion
Ransomware defense requires concerted effort across people, processes and technology. There is no silver bullet, but organizations can significantly reduce risk by securing the basics, layering security controls, training employees, practicing response plans, segmenting infrastructure and leveraging innovative technologies like deception and ransomware vaccines. Preparation and prevention up front is far easier than dealing with the aftermath of ransomware affecting critical systems and data. By taking a proactive stance, companies can develop resilience against attacks and quickly contain incidents. Ransomware thrives on lax security and ad hoc reactions, but organizations willing to invest in solid cybersecurity foundations can stay a step ahead of this threat.