Directory Traversal

Definition of Directory Traversal

Directory traversal, also known as path traversal, refers to a cyber attack technique that allows attackers to access restricted directories, files, and data within a system by exploiting insufficient validation of user-supplied input. By manipulating file paths, attackers can access and potentially modify files outside of the application’s intended scope. This vulnerability typically arises when inadequate security measures are in place, thus enabling unauthorized access to sensitive information.


The phonetics for the keyword “Directory Traversal” can be represented as:/dəˈrɛktəri trəˈvɜrsəl/Here’s a breakdown of the phonetics:- Directory: /dəˈrɛktəri/- Traversal: /trəˈvɜrsəl/

Key Takeaways

  1. Directory Traversal, also known as Path Traversal, refers to a security vulnerability that enables attackers to access restricted directories and execute commands outside of the web server’s root directory.
  2. This vulnerability commonly occurs due to insufficient input validation and weak application configurations, allowing attackers to exploit system files, access sensitive data, and perform unauthorized actions on the web server.
  3. To prevent Directory Traversal attacks, developers should implement proper input validation, utilize secure programming techniques, and follow best practices for configuring web server settings, such as ensuring permissions are set correctly and restricting access to sensitive directories.

Importance of Directory Traversal

The technology term “Directory Traversal” is important because it refers to a critical security vulnerability that arises when unauthorized access to an application’s file and directory structures is gained by a user or attacker.

This vulnerability exposes sensitive data and exposes the system to potential data loss, tampering, or corruption.

Knowledge of directory traversal helps developers to implement appropriate security measures such as input validation, server-side navigation restrictions, and file access controls, thereby ensuring the protection of valuable information and maintaining application integrity.

Furthermore, it helps system administrators and security professionals in understanding the potential risks and safeguarding their infrastructure from malicious attacks.


Directory traversal, also referred to as path traversal, is a technique predominantly employed in the realm of computer security. Its primary purpose is to assist in discovering and exploiting potential vulnerabilities within web applications and servers. Essentially, directory traversal allows authorized and unauthorized users to delve into a system’s hierarchy and access restricted directories or files.

By exploiting weaknesses in a system’s file access control, users can acquire sensitive information and potentially compromise the application or server in question. To achieve this, the attacker manipulates a targeted URL or input field with specific commands designed to access unauthorized areas. From the perspective of a security researcher or ethical hacker, directory traversal is a valuable tool in identifying security flaws and fortifying systems against potential attacks.

By actively engaging in directory traversal tactics, these professionals can evaluate the efficacy of safeguards put in place, subsequently pinpointing areas of improvement before a real-world breach occurs. Conversely, the same technique poses a significant threat when wielded by malicious actors. In their hands, the objective is to exploit vulnerabilities for nefarious purposes, such as data theft, sabotage, or other forms of unauthorized access.

Thus, understanding and being vigilant in relation to directory traversal are crucial aspects of a robust cybersecurity strategy.

Examples of Directory Traversal

Directory traversal, also known as path traversal, is a vulnerability in web applications, web servers, or file systems that allows an attacker to access unauthorized directories or files by manipulating the file path. Here are three real-world examples of directory traversal vulnerabilities and attacks:Apache Tomcat Vulnerability (CVE-2021-25329):In early 2021, a directory traversal vulnerability was discovered in Apache Tomcat software. An attacker could exploit this vulnerability by sending a specially crafted request containing directory traversal characters such as “..” to obtain unauthorized access to sensitive files, including application source code and configuration files. The vulnerability was subsequently patched.

Microsoft IIS0 Web Server Vulnerability (CVE-2017-7269):In 2017, Microsoft’s Internet Information Services (IIS) version

0 was found to have a directory traversal vulnerability, which allowed attackers to execute arbitrary code with elevated privilege. Cybercriminals could exploit this security flaw by sending malicious requests containing directory traversal payloads to gain unauthorized access to files on the server. Microsoft released an update to patch the vulnerability.TP-Link Router Vulnerability (CVE-2017-13772):TP-Link routers were found to have a directory traversal vulnerability in their web interfaces, which allowed a remote attacker to read arbitrary files on the router’s file system. This vulnerability was exploited by malicious actors to access sensitive details such as login credentials, WiFi passwords, and device configurations. TP-Link later released a firmware update to fix this security flaw.These examples demonstrate how widespread and damaging directory traversal vulnerabilities can be, emphasizing the importance of regular security assessments and software updates to prevent unauthorized access to critical systems.

FAQ: Directory Traversal

What is Directory Traversal?

Directory traversal, also known as path traversal, is a security vulnerability that allows an attacker to access files and directories on your web server that are outside the root folder. This can lead to unauthorized access to sensitive data, server configurations, or even complete control over your server.

How does a Directory Traversal attack work?

A directory traversal attack works by exploiting insufficient security validation of user-supplied input file names. Attackers can manipulate a web application’s intended file operations, to read or write files outside of the intended file directory, or execute system commands through malicious inputs.

How can I prevent Directory Traversal attacks on my web application?

To prevent directory traversal attacks on your web application, follow these guidelines:
1. Properly validate and sanitize user input to avoid malicious characters.
2. Implement proper access controls for file systems and directories.
3. Store sensitive data and configuration files outside the webroot.
4. Employ proper error handling to avoid exposing sensitive information in error messages.

What are some common Directory Traversal attack patterns?

Some common directory traversal attack patterns include:
1. Double-dot-slash (../) which is used to move up one directory level.
2. Triple-dot-slash (../../) which is used to go up multiple directory levels.
3. Percent encoding (%2e%2e%2f) which can bypass certain input checks.
4. Using null bytes (%00) to bypass file extension checks.
5. Exploiting insecure direct object reference (IDOR) vulnerabilities.

How can I detect Directory Traversal attacks on my server?

To detect directory traversal attacks on your server, consider implementing the following measures:
1. Use intrusion detection systems (IDS) to monitor server logs for suspicious activities.
2. Regularly review server logs for unusual file access patterns.
3. Use web application firewalls (WAF) to block specific attack vectors.
4. Continuously monitor application performance and security to detect unauthorized file operations.

Related Technology Terms

  • Path Manipulation
  • File System Navigation
  • Server-Side Request Forgery (SSRF)
  • Access Control Bypass
  • Canonicalization Attack

Sources for More Information


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