Day 11: Auditing Linux Privilege Escalation Vectors 🕵️‍♂️

Today, I moved into the "Red Team" mindset. If you want to build a secure system, you need to understand how an attacker thinks when they are trying to escalate privileges from a low-level user to root.

🛠️ The Security Auditor's Toolkit

Today’s session focused on identifying and testing specific vulnerabilities. Here are the core vectors I audited:

1. PATH Hijacking

If a system script runs tar instead of /usr/bin/tar, an attacker can manipulate their $PATH to point to a malicious binary.

• The Audit Rule: Always use absolute paths in your cron jobs and service configuration files.

2. The SUID Trap

SUID binaries run with the privileges of their owner.

• The Dangerous Binaries: If an attacker can execute a shell from within binaries like vim, find, or tar that have the SUID bit set, they gain root access instantly.
• Verification: I used this command to audit the system:

find / -perm -4000 -type f 2>/dev/null

3. Cron & Group Vulnerabilities

The "Golden Rule" of escalation: Writable Script + Root Execution = Root Access.
I simulated an attack where I had group-write permissions on a root-owned backup script. By injecting a command (chmod +s /bin/bash), I turned a simple script into an escalation vector.

Follow my journey: #1HourADayJourney