Client Side Path Traversal

👉 Overview

👀 What ?

Client Side Path Traversal (CSPT) is a type of cyberattack where an attacker manipulates the file path in a URL to gain unauthorized access to files and directories that reside outside the web root folder. This type of attack is also known as directory traversal or path traversal.

🧐 Why ?

Understanding CSPT is important as it is a common attack vector which can lead to unauthorized access to sensitive information, data exfiltration and potentially a complete system compromise. It is critical for developers and security professionals to understand this technique to prevent, detect and respond to such attacks.

⛏️ How ?

CSPT attacks are conducted by manipulating variables that reference files with 'dot-dot-slash (../)' sequences and its variations. For instance, an attacker can change the URL parameter from 'http://example.com/app?action=../login' to 'http://example.com/app?action=../etc/passwd' to gain unauthorized access to the 'passwd' file, which contains sensitive user information.

⏳ When ?

The use of CSPT attacks has been prevalent since the early days of the internet, primarily due to the lack of proper input validation and sanitization in web applications. Despite advancements in web security practices, such attacks are still commonly encountered today.

⚙️ Technical Explanations

CSPT attacks exploit the lack of proper input/output sanitization in the web application's path traversal operations. This allows an attacker to read, write, or delete files that they should not have access to. The attacker uses special characters such as '../' or '..\' to traverse up to parent directories. In a successful attack, the attacker could potentially gain access to sensitive files, such as configuration files, system files, or database files, leading to a potential system compromise. To mitigate such attacks, it is crucial to implement proper input validation and sanitization, use least privilege principle for file operations and regularly update and patch the system.