Lockdown Lab #36 CRITICAL Linux (Ubuntu/RHEL)

Enable and configure auditd

Enable and configure auditd

Attackers love operating in the dark. If you’re not logging critical security events on your Linux servers, you’re handing them a permanent stealth cloak. Remember SolarWinds? Lack of comprehensive audit logging on some endpoints delayed detection by months.

This isn’t rocket science, but I still see far too many organizations leaving their Linux boxes practically blind. auditd is your eyes and ears. It tracks file access, system calls, privilege changes – the exact trails attackers try to cover. Without it, post-exploitation tools like LinPEAS will notice and adjust their evasion tactics accordingly. Don’t make it easy for them.

Install it, enable it, configure it. It’s a foundational control, not an optional extra.

On Debian/Ubuntu systems, it’s a few simple commands: sudo apt install auditd audispd-plugins sudo systemctl enable auditd sudo systemctl start auditd

This is basic security hygiene. If you’re not doing this, you’re running a severe risk of missing the warning signs of a breach until it’s too late.

The fix

sudo apt install auditd audispd-plugins  # Debian/Ubuntu

sudo systemctl enable auditd

sudo systemctl start auditd

# Key rules (/etc/audit/rules.d/audit.rules):

-w /etc/passwd -p wa -k identity

-w /etc/shadow -p wa -k identity

-w /var/log/auth.log -p wa -k auth_log

-a always,exit -F arch=b64 -S execve -k exec

Reference: CIS Linux Benchmark 4.1

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