System activity check

 ,sudo apt update && sudo apt install clamav -y

sudo freshclam # Update virus database

sudo clamscan -r /home/ # Scan home directory

It looks like you might be asking about "threats" in Linux. If you're looking for ways to check for security threats or malware on a Linux system, here are some methods:

1. Check Running Processes

Use the following commands to check for unusual processes:

ps aux --sort=-%cpu | head -20 # Check top CPU-consuming processes

ps aux --sort=-%mem | head -20 # Check top memory-consuming processes

2. Check Open Network Connections

See active network connections and detect suspicious activity:

netstat -tulnp

ss -tulnp

lsof -i

3. Check System Logs

Look for unusual logs in system files:

journalctl -xe

dmesg | less

cat /var/log/syslog | less

4. Use ClamAV for Malware Scanning

ClamAV is an open-source antivirus for Linux:

sudo apt update && sudo apt install clamav -y

sudo freshclam # Update virus database

sudo clamscan -r /home/ # Scan home directory

5. Use rkhunter for Rootkit Detection

Rootkit Hunter can detect hidden threats:

sudo apt install rkhunter -y

sudo rkhunter --update

sudo rkhunter --checkall

6. Check for Unauthorized Users or SSH Logins

who

last -a

cat /var/log/auth.log | grep "Failed password"

If you want to check for threats on a Linux machine remotely (online access PC), you can follow these steps:

1. Access the Remote System

Use SSH (Secure Shell) to log into the remote Linux machine:

ssh username@remote_ip_address

Replace username with the actual username and remote_ip_address with the IP of the system.

2. Check for Suspicious Processes

Once logged in, use these commands:

ps aux --sort=-%cpu | head -20 # Check top CPU-consuming processes

ps aux --sort=-%mem | head -20 # Check top memory-consuming processes

3. Scan for Malware (ClamAV)

If ClamAV is installed on the remote system, run:

sudo clamscan -r /home/

4. Check Active Network Connections

Look for suspicious network activity:

netstat -tulnp

ss -tulnp

lsof -i

5. Analyze System Logs for Intrusions

journalctl -xe # Check system logs

cat /var/log/auth.log | grep "Failed password" # Check failed login attempts

6. Use Rootkit Detection Tools

If rkhunter is installed, scan for rootkits:

sudo rkhunter --checkall

7. Use Online Security Tools (If Remote GUI Access Available)

If you have GUI access (e.g., via TeamViewer, AnyDesk, or RDP), you can use:

VirusTotal (upload suspicious files for scanning)

Malwarebytes for Linux (if installed)

Chkrootkit (another rootkit scanner)