The scenario described, where Oscar receives an email with a link that contains a malicious URL

redirecting to evilsite.org, exemplifies a vulnerability related to unvalidated redirects and forwards.

This type of vulnerability occurs when a web application accepts untrusted input that could cause the

web application to redirect the request to a URL contained within untrusted input. Attackers can

exploit this vulnerability by crafting a malicious URL that leads unsuspecting users to phishing sites or

other malicious websites, under the guise of a legitimate domain. This is distinct from malware,

which refers to malicious software; SQL injection, which involves inserting malicious SQL queries

through input fields to manipulate or exploit databases; and is not a term related to cybersecurity

vulnerabilities.

Reference:The Incident Handler (ECIH v3) certification materials often cover web application

vulnerabilities, including unvalidated redirects and forwards, emphasizing the need for proper

validation and sanitization of user input to prevent such exploits.