When it comes to keeping your Linux server secure, there are a variety of tools available to scan for malware and security flaws. Here are some of the best tools to consider.

1. ClamAV – ClamAV is a popular open-source antivirus software that is designed to detect and remove malware on Linux servers. It is highly effective at detecting viruses, trojans, and other types of malware, and can be configured to perform regular scans and updates.

2. Lynis – Lynis is a powerful security auditing tool that can identify potential security flaws on Linux systems. It scans for vulnerabilities in the system configuration, network settings, and installed software, and provides detailed reports on any issues that are found.

3. OpenVAS – OpenVAS is a vulnerability scanner that can detect security risks on Linux servers, including outdated software, unsecured ports, and weak passwords. It also provides a web interface for managing scans and generating reports.

4. RKHunter – RKHunter (Rootkit Hunter) is a tool that scans for rootkits and other types of malicious software on Linux servers. It performs a variety of checks to identify potential security threats, including checking system files for changes and looking for unauthorized accounts.

5. Tripwire – Tripwire is a file integrity monitoring system that can detect changes to critical system files and directories. It can be configured to send alerts when unauthorized changes are detected, making it useful for detecting malware and other security threats.

6. Nmap – Nmap is a network exploration and security auditing tool that can scan Linux servers for open ports, running services, and potential vulnerabilities. It is highly customizable and can be used to perform a variety of security-focused tasks, including host discovery, port scanning, and version detection.

7. AIDE – AIDE (Advanced Intrusion Detection Environment) is a file and directory integrity checker that can detect changes to critical system files and directories. It can be used to detect unauthorized changes to configuration files, binaries, and other important system resources.

Overall, these tools can help you scan your Linux servers for malware and security flaws, and provide you with the information you need to keep your systems secure. By regularly scanning and auditing your servers with these tools, you can help ensure the integrity of your data and protect against potential threats.