Identify the attack when an attacker by several trial and error can read the contents of a password file present in the restricted etc folder just by manipulating the URL in the browser as shown: http://www.terabytes.com/process.php./../../../../etc/passwd

The attack shown uses the ../ sequence in a URL to navigate up the server's file system hierarchy. This technique is a classic example of a Directory Traversal (or Path Traversal) attack. The goal is to bypass the web server's access controls and access files and directories stored outside of the intended web root directory. In this specific example, the attacker is attempting to read the /etc/passwd file, which contains a list of user accounts on a Unix-like system. This vulnerability typically arises from insufficient validation of user-supplied input.

B: A SQL Injection attack involves inserting malicious SQL queries into an application's input to manipulate the backend database, not traverse the file system. C: A Denial-of-Service attack's primary goal is to make a system or service unavailable to legitimate users, not to read sensitive files. D: Form Tampering involves modifying data within HTML form elements, such as prices or quantities, before submission, which is different from manipulating a URL path.

1. OWASP Foundation. (n.d.). "Path Traversal." OWASP Community Pages. Retrieved from https://owasp.org/www-community/attacks/PathTraversal. (This is a globally recognized standards body for web security, equivalent to official documentation in this domain).

2. Vick, K. (2014). Lecture 10: Web Security. MIT 6.858 Computer Systems Security, Fall 2014. Massachusetts Institute of Technology: MIT OpenCourseWare. Slides 21-23 describe Path Traversal attacks.