URLinjektion

URLinjektion is a type of security vulnerability that arises when a web application improperly handles user-supplied data within a URL. This vulnerability allows attackers to inject malicious code or commands into the URL, which can then be executed by the server or the user's browser.

The most common form of URLinjektion involves manipulating parameters within a URL. For example, if a web application uses a URL parameter to specify a file to be displayed, and it does not properly validate or sanitize the input, an attacker could inject a path traversal sequence (like "../") to access sensitive files outside the intended directory.

Another variant is when user input in a URL is directly reflected in JavaScript code displayed to the user. This can lead to cross-site scripting (XSS) attacks, where the attacker injects malicious JavaScript that can steal cookies, hijack sessions, or redirect users to phishing sites.

Preventing URLinjektion typically involves strict input validation and output encoding. Developers should always sanitize user-supplied data before using it in file paths, database queries, or any other sensitive operation. Output encoding ensures that any potentially malicious characters are displayed as plain text rather than being interpreted as code by the browser or server. Regular security audits and penetration testing are also crucial to identify and mitigate such vulnerabilities.