What is Malware Detection?

What is malware detection

Malware detection involves strategies and tools for identifying and analyzing malware threats in a system or network. Malware threats evolve in complexity and sophistication, posing significant risks to individuals and organizations. As a primary security risk, malware exploits system vulnerabilities and manipulates users through attack vectors to infiltrate or damage computer systems. Common issues like misconfigurations, clicking suspicious links, or using weak credentials expose users and organizations to these attacks.

With the escalating threat landscape, malware detection becomes a critical component of the cybersecurity ecosystem, protecting systems from potential compromise. By gaining insights into how malware operates and recognizing the indicators of compromise (IoC), you can implement proactive security measures to protect your digital environment.

What is malware

Malware, short for malicious software, is any intrusive software intentionally designed to disrupt a computer system or network. Threat actors deploy malware to steal sensitive information, disrupt operations, or achieve financial gains. The cybersecurity ecosystem includes a wide range of malware, including ransomware, worms, viruses, rootkits, spyware, adware, and trojans. Though unique in their characteristics and methods of operation, they all share a common aim of compromising the integrity, confidentiality, or availability of data.

Working principle of malware

Malware is designed to infect systems and networks to disrupt and steal information or resources. It operates through various mechanisms depending on its type and purpose. Malware works using the following common techniques:

• Infection vector (attack vector): This is the method threat actors use to spread malware, exploit system vulnerabilities, and steal data. Malware spreads through various vectors, such as compromised credentials, email attachments, fake software updates, malicious downloads, infected websites, or removable media. Social engineering tactics may also trick users into executing the malware.
• Exploiting vulnerabilities: Some malware exploits security flaws in software or operating systems to gain initial access. Some of these vulnerabilities include unpatched software, weak passwords, or misconfigurations.
• Payload delivery: After gaining access, malware typically delivers its payload, which is the part of the malware designed to perform malicious action. These actions could include remote code execution, data exfiltration, or file encryption (as in ransomware).
• Persistence mechanisms: Malware may install itself in multiple locations or modify system settings to ensure it remains active even after a reboot or removal attempt.
• Communication with external systems: Some malware is designed to remotely control a system by communicating with command and control (C2) servers to receive instructions or send stolen data. This communication may be encrypted to preserve data integrity.
• Defense evasion: Malware often uses various techniques to avoid detection by antivirus software and security systems. This can include obfuscation (hiding its code), polymorphism (changing its code with each infection), or sandboxing (hiding its presence in a controlled environment).
• Self-replication: Some malware, like worms, replicate themselves and spread to other systems and networks without user intervention, often exploiting network vulnerabilities.

Common types of malware

Understanding malware types can help you prioritize the threats and create appropriate defensive controls. Below are common malware types, including their methods of operation and potential impacts.

• Ransomware: This malware type encrypts files on a computer or network and demands a ransom for restoration. They are often spread through phishing emails or malicious downloads. Ransomware exploits human and software vulnerabilities to infect endpoints, leading to data loss or financial harm. An example of a prominent outbreak is the WannaCry ransomware, which affected thousands of computers worldwide in 2017.
  
  Ransomware is a business model called Ransomware as a service (RaaS). It is made available to threat actors in a subscription-based model, where a percentage of the ransom is shared with the malware developers. Some well-known examples of RaaS include Cerber, Hive, DarkSide, and Shark.
• Worms: This type of malware is designed to infect a computer, replicate itself, and spread to other computers across the networks. Worms exploit vulnerabilities in software and networks to infect computer systems and other devices, and can consume bandwidth and slow down or crash networks. Infected systems can be part of a larger attack, such as a distributed denial of service (DDoS). Common examples of worms include Conficker and NgrBot.
• Viruses: This malware type attaches to legitimate programs or files and spreads to other systems when the infected program is executed. A virus requires user action, such as opening an infected file to begin execution. Viruses are designed to disrupt a system's operating ability, causing significant operational issues and data loss. An example is the ILOVEYOU virus, which infected millions of computers by exploiting vulnerabilities on Windows.
• Trojans (Trojan horse): This is a type of malware that masquerades as legitimate software with ulterior motives to disrupt system operations. Trojans are packaged with additional malware types including backdoors, rootkits, ransomware, and spyware. They trick users into installing them, creating backdoors for attackers to access the system, steal data, or join botnets. For instance, the Zeus trojan is known for stealing banking credentials.
• Adware: Software designed to throw unwanted advertisements or pop-up windows to users, most often within web browsers. They are often bundled with free software that can infect your system and steal data. Adware is not always harmful. However, it can lead to more serious malware infections as they redirect browsers to unsafe websites.
• Spyware: Spyware is malicious software that secretly runs on a computer, captures, and transmits confidential information to its author without the user's consent. Spyware is bundled with legitimate software or downloaded unknowingly. For example, keyloggers are spyware that records keystrokes to capture passwords and credit card information.
• Fileless malware: As the name suggests, this type of malware does not rely on files to execute, but resides in a computer's memory. It uses legitimate programs to infect a computer system, leaving minimal footprints to detect after execution. This mode of operation makes it difficult for forensic investigations. An example of fileless malware is the DNSMessenger.
• Rootkits: These are malicious tools that allow unauthorized users to gain control of a computer system while hiding their presence. Rootkits employ sophisticated techniques to conceal their presence, such as kernel modification and API hooking, along with their ability to maintain persistent access to compromised systems. These methods allow rootkits to operate undetected, making them a significant threat to system security. They can infect a system through social engineering attacks such as phishing. Notable examples of rootkits include FudModule, Knark, and Zero Access.

Indicators of malware infection

Malware detection can be a challenging process, but several common symptoms may indicate a system has been compromised. Here are some key indicators to look out for:

• High CPU, GPU, or memory usage of processes.
• Unusual system behavior, such as frequent crashes or slow performance.
• Unusual pop-ups and ads can indicate adware or other malware types.
• Connection to known malicious IP addresses or hostnames can indicate malware communicating with a remote server.
• Disabled security software such as antivirus or firewall.
• Encrypted files can indicate the presence of ransomware.
• Unauthorized access to accounts or unusual login attempts.
• Presence of unfamiliar programs or applications you did not install.
• Changes to browser settings may indicate the presence of browser hijackers.
• Frequent browser redirects to unfamiliar websites or search engines when trying to access known sites can signify a browser hijacker.

Benefits of malware detection

Malware detection plays an important role in protecting organizations from security breaches. Some benefits of implementing a robust malware detection strategy include the following.

• Malware detection protects assets by preventing data breaches and identity theft, safeguarding proprietary information, user credentials, and credit card numbers from compromise.
• Malware detection is cost-effective as it saves time, resources, and effort to respond to attacks.
• Proactive detection monitors code behavior and system operations, providing security teams insights into malware characteristics to effectively handle known and emerging threats.
• Malware detection contributes to cyber threat intelligence by correlating data from various sources, such as network traffic, user behavior, and historical incidents, to identify patterns indicative of malware activity.
• Malware detection enhances advanced analytics and reporting by enabling security teams to prioritize their efforts, identify critical vulnerabilities, and improve resource allocation strategies.
• Timely detection of malware facilitates quick incident response, minimizing damage and restoring normal operations efficiently.
• Many organizations are subject to regulations requiring sensitive data protection, making effective malware detection essential for compliance with standards like GDPR, HIPAA, and PCI DSS.
• Detecting malware attacks is essential for maintaining system integrity and ensuring optimal functionality, which upholds your organization's reputation for being trustworthy and secure.

Malware detection techniques

Detecting malware involves a combination of expertise and technologies. Cybersecurity experts employ several malware detection techniques. Some of the main techniques are listed below.

• Signature-based detection: This technique uses known indicators of compromise (IoC), such as file hashes, domain names, IP addresses it contacts, or strings within the executable to identify malware. It relies on a database of known malware signatures to identify threats, flagging a file as malicious when it matches a signature in the database. This technique is commonly used by traditional antivirus software.
  
  This malware detection technique is effective as it has a low false-positive rate. However, it is reactive and unable to identify zero-day threats and new sophisticated malware variants. In addition, any modification to an existing and known malware sample renders this technique ineffective as the malware signature changes.
• Behavior-based detection: This malware detection technique involves looking for unusual activities to identify the presence of malware during execution on a system. Malware exhibits unusual file, registry, and network activities, such as opening and encrypting files, deleting files, exfiltrating large volumes of data, and more. This technique detects new or modified malware that may not have a known signature.
• Heuristic-based detection: Heuristic analysis detects malware by analyzing the code or behavior of a program. This method is mainly used by antivirus and security software to identify and detect potentially malicious files or behaviors based on predefined rules and patterns.
• Machine Learning and Artificial Intelligence (ML/AL): This technique involves training machine learning algorithms on data that includes both benign and malicious hardware behavior to classify new hardware activities as either benign or malicious. This technique can detect previously unknown threats and adapt to new malware variants.

Best practices for malware detection

Protecting against malware is essential for maintaining the security and integrity of systems and data. Here are several effective strategies to help safeguard against malware infections.

• Monitor your systems and use security software: Regularly review account activity and system logs for any signs of unusual behaviors, such as unexpected pop-ups, unauthorized access, performance deterioration, and more. Additionally, install reputable antivirus software that offers real-time protection and regular updates.
• Regularly update your frontline defenses: Patch systems quickly, as security flaws become well-known once the updates are released. This action ensures all software, including operating systems, browsers, and plugins, are protected against vulnerabilities. In addition, install two-factor authentication (2FA) as a first line of defense.
• Use firewall systems: Configure firewall systems to monitor incoming and outgoing traffic. This strategy helps to block all malware injection attacks and unauthorized access to your network.
• Implement next-generation monitoring tools: Deploy intrusion detection systems (IDS), and intrusion prevention systems (IPS) that monitor network traffic for suspicious activity and potential threats. This practice helps to prevent unauthorized access or malware activity.
• Educate users on threat sources: Keep updated with the latest malware trends and tactics threat actors use. Also, train users on whom and what to trust and teach them not to fall for phishing or other schemes. Users should avoid opening suspicious links in unsolicited emails or messages, which may lead to phishing sites or malware downloads.
• Avoid risks: Avoid visiting unfamiliar websites to download free products like apps, music, movies, or games that might expose you to malware. Scan all external devices with a security program before using them.
• Regularly back up data and validate restoration: Use external hard drives or cloud storage solutions to store copies of your critical data to prevent data loss. It is also important to ensure your backups can be restored appropriately when needed.
• Segment your network: Reduce the risk of outbreak exposure by dividing your network into smaller parts. This strategy isolates different parts of the network with better traffic control.
• Enforce the principle of least privilege: Use standard user accounts and avoid using administrator or root accounts for everyday tasks to limit the potential impact of malware.
  
  Also, restrict user's permissions from accessing certain system resources and implement Zero Trust.

By leveraging the information in this comprehensive guide, you can better protect your systems against malicious threats and ensure a proactive security posture. Wazuh offers malware detection capability, providing insights into how to implement these detection techniques.