Path Traversal Attacks: How Hackers Exploit Directory Flaws to Access Server Files

Path traversal, also known as directory traversal, is a web security vulnerability that allows attackers to read or write arbitrary files on a server running an application. By manipulating file path parameters with sequences like "../", an attacker can navigate outside the intended directory and access sensitive files such as credentials or operating system data. In severe cases, write access can enable attackers to modify application behavior and gain full control of the server. While many applications implement defenses such as stripping traversal sequences or enforcing base directory rules, these protections can often be bypassed using techniques like URL encoding, nested sequences, or absolute path references. Both Unix and Windows systems are susceptible, making path traversal a critical vulnerability that developers must address with robust input validation.