A robust malware prevention and detection strategy is critical to cyber security and cyber resilience today. After all, a single malware infection can inflict serious financial damage — from business disruptions and remediation costs to lasting reputational damage and customer churn.
To help, this blog explains the types of malware organizations need to defend against and the common vectors for deployment. Then it offers effective ways to prevent malware from gaining a foothold in your network, as well as strategies that will help you detect and remove malware that manages to sneak through your defenses.
What Is Malware?
Simply put, malware is malicious software inserted into a system, usually covertly, in order to annoy or disrupt the victim. In many cases, malware is designed to compromise the confidentiality, integrity or availability of the victim’s data or applications. Windows devices are top targets because the operating system is so widely used, but any connected endpoint can be a target for malware-related cyberattacks.
There are many different types of malware, including the following:
- Viruses — A virus is designed to replicate itself and spread to other computers, with or without human intervention.
- Ransomware — Cybercriminals use ransomware attacks to encrypt a victim’s sensitive data so they can demand a ransom for the decryption key.
- Spyware — Spyware gathers information about a victim without their knowledge.
- Adware — Adware automatically delivers advertisements to generate revenue for its creator or a third party. It is often used in conjunction with spyware.
- Worms — Worms are one of the most common and most dangerous types of malicious software because they can replicate themselves without being attached to a program or run by a user.
- Trojans — Trojans are malware disguised as legitimate programs or files in order to entice users to install them.
- Rootkits — Rootkits are used to remotely control systems and facilitate additional access during extended attacks.
- Keyloggers — This surveillance software captures a user’s keystrokes to steal passwords and other sensitive information.
- Cryptojacking software — Cryptojacking malware attacks exploit a victim’s computing hardware to perform the complex calculations necessary to mine cryptocurrency.
- Rogue software — Using rogue software, cybercriminals attempt to scam a user into believing their device is infected with malware and convince them to pay for its removal.
- Scareware — Scareware displays an alarming message to frighten users into taking actions that ultimately lead to them being scammed.
Common Malware Vectors
To deploy malware, threat actors take advantage of vulnerabilities in both systems and human nature. Common malware vectors include:
- Phishing emails — Employees receive email messages that entice them into opening a malicious attachment disguised as a legitimate file, which deploys malware on the user’s computer.
- Social engineering — Adversaries gather information about their intended victims, such as potential points of entry and weak security protocols, and then use psychological manipulation to trick users into making mistakes like clicking on malicious links that download malware.
- Free offerings — Downloading files from untrusted sources that advertise free software, games or other media can introduce malware to a system.
- Drive-by downloads — Both malicious and legitimate websites can contain malicious code that is downloaded to anyone visiting the site.
- Removable media — Adversaries can plant malware on USB drives and similar media so that it will be transferred to a victim’s computer when they insert it.
Preventing Malware Infections
Fortunately, there are proven defensive measures against malware attacks you can take to reduce the risk of malware infections. Indeed, the following approaches are effective for defending against a wide variety of cyberattacks, not just malware.
Update systems regularly.
A core best practice for defending against malware is to keep your systems up to date. Promptly validate and install all new security-related patches to close new vulnerabilities that have been discovered. Be sure to include all operating systems, software tools, browsers and plug-ins in your patching regimen.
Perform regular security audits.
Regular security audits help you proactively identify and address vulnerabilities, such as potential entry points for attacks, unused accounts and devices, and misconfigurations that malware can take advantage of.
Improve the security of user accounts.
Require all accounts to have strong, unique passwords. When establishing your password policy, be sure to review current password best practices concerning criteria such as length, complexity and expiration. Consider providing users with a secure password manager tool so you can adopt strong password policies without increasing business disruptions and password-related helpdesk tickets.
In addition, enable multifactor authentication (MFA). MFA requires at least two authentication methods, such as a password plus a biometric like a fingerprint, voiceprint or iris scan.
Educate all users.
To reduce the risk that users will be tricked into unleashing malware into your network, be sure to:
- Educate everyone about common malware attacks, including how to identify suspicious emails that could be a phishing campaign.
- Promote safe internet browsing habits. In particular, teach users how to recognize credible sites and what to do if they stumble onto something that that seems suspicious.
- Explain why it’s important for users to report unusual system behavior and make it easy for them to do so.
- To improve the security of the mobile workforce, require users to join only secure networks and to use VPNs when working outside the office.
Implement layered security tools.
To protect against cyber security threats, including malware, organizations need a robust set of security tools. They include:
- Next-generation firewalls (NGFWs) inspect network traffic at the application layer to identify and block malicious code and can use sandboxing to analyze suspicious files in an isolated, secure environment to test for malware.
- An intrusion prevention system (IPS) can automatically block known attack methodologies and abnormal traffic patterns.
- Endpoint monitoring tools provide real-time visibility into activity on endpoints to help detect malware.
- Antivirus software helps protect against malware by blocking viruses.
- Email security filters can scan and remove malicious attachments and suspicious embedded hyperlinks.
- Web filters can block access to websites known to host malicious content, before the user’s browser can make a connection.
Use network segmentation.
Network segmentation divides the network into multiple segments that are partitioned using internal firewalls and access policies. When malware infiltrates one of these segments, it is restricted from moving laterally into other segments of the network, limiting the damage it can do.
Adopt a Zero Trust security model.
Zero Trust requires nothing to be trusted by default; instead, all users and devices must be continually verified before being granted access to resources. This reduces the risk of malware spreading through compromised accounts or devices. Implementing MFA and network segmentation are solid first steps in a Zero Trust approach, and organizations can expand to other core Zero Trust strategies.
Keep up on new threats.
Cybersecurity is a moving target. This is especially true for malware, as new strains and versions are constantly being released. Staying on top of current trends helps organizations fortify their defenses, as well as to remain compliant with industry regulations and standards, which often evolve alongside the threat landscape.
Detecting Malware Infections
Even the best malware prevention strategy cannot guarantee that no malware will get through. Adversaries do their best to avoid detection, but there are some telltale signs that a device is infected. Be sure to teach users to watch for the following:
- Performance issues — Like any application, malware uses memory and processing resources.
- Unexpected shutdowns or reboots — Malware can interfere with system processes and cause instability.
- Sudden increase in pop-up ads — This is a common sign of adware.
- Unexpected changes — A new homepage, additional toolbars or a change in your default search engine are common indicators of malware infection.
- Excessive internet activity — Unusual activity, especially when you’re not using your computer, may indicate that spyware or other malware is sending data or communicating with a remote attacker.
Automating Malware Detection
In addition to educating users about these signs of malware infection, organizations should consider investing in security solutions that offer advanced security analytics to alert you automatically to threats. These solutions analyze a wide range of data sources to establish normal behavior of users and systems. By continually comparing current activity to those baselines, the tools can promptly identify anomalies and patterns indicative of an attack.
Sandboxing
Sandboxing is a method for executing suspicious programs and opening suspicious files in an isolated environment to determine if they are malicious and learn about the attack.
Handling a Malware Infection
Of course, it’s not enough to know how to avoid malware infections and detect threats in progress; organizations also need to know how to stop malware attacks. An effective response often includes multiple strategies.
Shutting Down the Immediate Threat
As soon as a malware attack has been spotted, all infected devices should be disconnected from the network to prevent the malware from spreading. Any user accounts that were involved in the attack should immediately have the current session terminated and their credentials reset.
Wiping and Restoring Devices
All infected systems should be wiped. A new operating system must be installed and data should be restored from backup. To avoid reinfection, verify that backups are clean before using them.
Keep in mind that ransomware attackers often target a company’s backup systems in preliminary attacks to prevent data restoration. Accordingly, protect your backups with extra security measures and make sure to conduct test restores on a regular basis.
Seeking Professional Help
Every organization needs an incident response plan that outlines the step-by-step measures to take when an attack is identified. The plan should also include a list of professionals to contact, such as cybersecurity experts, attorneys and insurance companies.
How Netwrix Can Help
Netwrix provides a suite of solutions that can help you fortify your cybersecurity to block malware infections and get the comprehensive visibility you need to promptly detect and respond to threats in progress. Here are some solutions to check out:
- Netwrix Enterprise Auditor can help you minimize your attack surface and avoid malware infections by proactively identifying and automatically fixing conditions that put valuable data at risk.
- Netwrix Endpoint Protector helps keep malware from exfiltrating valuable data through USB storage devices, email, browser uploads, enterprise messaging apps and more.
- Netwrix StealthINTERCEPT can alert your team in real time about suspicious changes, authentications and other events that could indicate malware or another threat.
- Netwrix password security software offers a broad range of capabilities. In particular, it empowers you to protect accounts with strong password policies and supply users with a powerful password manager so they can adhere to those policies easily.
- The Netwrix ransomware solution can catch a ransomware attack before it can alter your data.
Plus, Netwrix solutions integrate readily with SIEMs and other security tools, supporting a holistic security approach that provides comprehensive intelligence for better threat prevention, analysis and response.
Conclusion
Cybercriminals are constantly creating new malware variants and looking for more effective strategies for unleashing it in corporate networks. So it’s no wonder than many organizations are eager to learn how to prevent malware attacks.
But there is no single answer to the question of how to avoid malware. Rather, organizations need a comprehensive approach that includes strategies for preventing infections as well as detecting and responding to attacks. By following the best practices outlined in this blog and choosing the right tools, IT teams can reduce the risk from malware, as well as enhance their organization’s defense against other cyber threats.