Book Image

Privilege Escalation Techniques

By : Alexis Ahmed
5 (2)
Book Image

Privilege Escalation Techniques

5 (2)
By: Alexis Ahmed

Overview of this book

Privilege Escalation Techniques is a detailed guide to privilege escalation techniques and tools for both Windows and Linux systems. This is a one-of-a-kind resource that will deepen your understanding of both platforms and provide detailed, easy-to-follow instructions for your first foray into privilege escalation. The book uses virtual environments that you can download to test and run tools and techniques. After a refresher on gaining access and surveying systems, each chapter will feature an exploitation challenge in the form of pre-built virtual machines (VMs). As you progress, you will learn how to enumerate and exploit a target Linux or Windows system. You’ll then get a demonstration on how you can escalate your privileges to the highest level. By the end of this book, you will have gained all the knowledge and skills you need to be able to perform local kernel exploits, escalate privileges through vulnerabilities in services, maintain persistence, and enumerate information from the target such as passwords and password hashes.
Table of Contents (18 chapters)
1
Section 1: Gaining Access and Local Enumeration
6
Section 2: Windows Privilege Escalation
12
Section 3: Linux Privilege Escalation

Escalation via cron wildcards

This privilege escalation technique involves taking advantage of cron jobs that execute commands or scripts with wildcards. In the context of Linux, wildcards (*) are used to perform more than one action at a time, and they can be used in a variety of different ways. In this section, we will explore how they can be exploited to execute malicious commands or scripts if misconfigured.

Important Note

Note that the success of this technique will depend on whether or not wildcards have been utilized in cron jobs.

Follow these steps:

  1. The first step in this process involves identifying cron jobs that run commands or scripts with wildcards. Analyzing the crontab file reveals an interesting cron job that is responsible for creating and compressing backup archives:

    Figure 12.14 – Backup cron job

    As highlighted in the preceding screenshot, the cron job runs the compress.sh script located under /usr/local/bin as the root user and runs every minute...