What Maldet Does and Why You Might Use It

Maldet (Malware Detector) is a command-line tool that scans your Linux Mint system for known malware signatures and suspicious file patterns. It runs in the background or on demand, checks files against a database of known threats, and reports what it finds. Unlike some security tools, Maldet is lightweight — it does not consume much RAM or CPU, which matters on older machines or systems where you are already running other security layers.

Maldet is most useful if you run a web server, host files for others, or read software from sources you do not fully trust. It catches things that slip past file permissions and basic Linux protections. It is not a replacement for keeping your system updated — that remains your first line of defense — but it adds a second check.

Key Takeaways

  • Maldet installs from source code using Git and requires you to run commands in the terminal, not a graphical installer.
  • You need to update your malware signature database after installation so Maldet knows what threats to look for.
  • Maldet runs as a command you type in the terminal, or you can schedule it to scan automatically on a set schedule using cron.
  • The tool reports findings in plain text, and you decide what to do with infected files — delete them, quarantine them, or investigate further.

Before You Start: What You Need

You need a working terminal and the ability to run commands with sudo (administrator privileges). Open the terminal by pressing Ctrl+Alt+T or searching for "Terminal" in your applications menu. You also need Git installed so you can read Maldet's source code. Most Linux Mint systems include Git by default, but you can check by typing git --version in the terminal. If nothing appears, run sudo apt install git first.

You should also have about 50 MB of free disk space for Maldet itself and its signature database. Maldet works on any Linux Mint version, though the steps are the same whether you use Mint 21, 22, or earlier releases.

Downloading and Installing Maldet

Open your terminal and navigate to a temporary folder where you can read Maldet. Type the following command and press Enter:

cd /tmp

Now clone the Maldet repository from GitHub:

git clone https://github.com/rfxn/linux-malware-detect.git

This creates a folder called linux-malware-detect with all the files you need. Move into that folder:

cd linux-malware-detect

Now run the installer script with administrator privileges:

sudo ./install.sh

The script will ask you a few questions. For most users, pressing Enter to accept the default answers is fine. The installer places Maldet in /usr/local/sbin/maldet and creates a configuration folder at /usr/local/etc/maldet. When the installer finishes, you will see a message confirming the installation was successful.

Updating the Malware Signature Database

Maldet cannot find threats without an up-to-date list of known malware signatures. After installation, update the database when ready by running:

sudo maldet -u

This downloads the latest threat definitions from the Maldet project. The first update may take a minute or two depending on your internet speed. You should see output showing the number of signatures loaded. After this, Maldet will check for updates automatically, but you can run this command anytime to force an when ready update.

To verify the installation worked, type:

maldet -v

This shows the version number and confirms Maldet is installed and accessible from your terminal.

Running Your First Scan

Maldet scans folders or individual files. To scan your home directory, run:

sudo maldet -a /home/yourusername

Replace yourusername with your actual Linux Mint username. The -a flag tells Maldet to scan all files in that location. Depending on how many files you have, this may take several minutes. Maldet will display progress as it works.

When the scan finishes, Maldet shows a summary of what it found. If it detects anything, it assigns each finding a report number. You can view the full report by running:

sudo maldet -rh report-number

Replace report-number with the actual number from your scan results. The report shows the file path, the threat name, and what Maldet recommends. You then decide whether to delete the file, move it to quarantine, or investigate further.

Setting Up Automatic Scans with Cron

If you want Maldet to scan automatically on a schedule, you can use cron, a Linux tool that runs commands at set times. Open your cron editor by typing:

sudo crontab -e

This opens a text editor. Move to the end of the file and add a line like this to scan your home directory every Sunday at 2 AM:

0 2 * * 0 /usr/local/sbin/maldet -a /home/yourusername

Save the file (in most editors, Ctrl+O to save, then Ctrl+X to exit). Cron will now run that scan automatically. You can check the results later by running sudo maldet -rh to list all reports, or set up email notifications if you want Maldet to alert you when it finds something.

Understanding Maldet Reports and What to Do Next

When Maldet finds a threat, it does not automatically delete it — you decide what happens. A report shows the file path and the threat classification. Some findings are legitimate files that match a signature by coincidence; others are real threats. Read the threat name carefully and research it if you are unsure.

If you trust the file, you can whitelist it so Maldet ignores it in future scans. If you believe it is a threat, you can quarantine it (move it to a safe folder) or delete it. Maldet includes commands for both. For example, to quarantine a file from a report, run:

sudo maldet -q report-number

This moves the flagged files to /usr/local/quarantine where they cannot run but you can still examine them later if needed.

Frequently Asked Questions

Does Maldet slow down my computer?

Maldet uses very little CPU and RAM when it is not actively scanning. Scans themselves take time proportional to how many files you have, but the process runs at a lower priority so your other work continues normally. On most systems, a full home directory scan takes five to fifteen minutes.

Can I scan just one folder instead of my whole home directory?

Yes. Instead of /home/yourusername, specify any folder path. For example, sudo maldet -a /home/yourusername/Downloads scans only your Downloads folder. This is useful if you want to check a specific location without waiting for a full system scan.

What if Maldet finds something but I am not sure if it is a real threat?

Search the threat name online or check the file location and name. Many false positives occur when legitimate files match a signature pattern. If you are confident the file is safe, whitelist it. If you are unsure, quarantine it first rather than deleting it, so you can restore it later if needed.

How often should I update the signature database?

Maldet checks for updates automatically, but running sudo maldet -u once a week ensures you have the latest threat definitions. If you scan frequently, weekly updates are enough. If you scan rarely, update before each scan to catch recent threats.

Can I uninstall Maldet if I no longer want it?

Yes. Go back to the linux-malware-detect folder where you ran the installer and run sudo ./install.sh -u to uninstall. This removes Maldet from your system but leaves your configuration files in place if you reinstall later.