Description: Cross-Site Scripting (XSS) access acquisition is a security vulnerability that allows an attacker to inject malicious scripts into otherwise trusted web content. This technique relies on executing JavaScript code in a user’s browser, which can lead to the theft of sensitive information such as session cookies, user credentials, or personal data. XSS is classified into several categories, including reflected, stored, and DOM-based XSS, each with different attack methods and exploitation vectors. The nature of XSS lies in the trust users place in the websites they visit, allowing attackers to manipulate the content presented to users. Exploiting this vulnerability can have severe consequences, such as identity theft, account impersonation, and malware propagation. Therefore, it is crucial for developers to implement appropriate security measures, such as input validation and sanitization, as well as the use of Content Security Policies (CSP) to mitigate the risks associated with XSS.
History: The XSS vulnerability was first identified in the late 1990s when web browsers began allowing script execution on pages. As the web evolved, so did attack techniques, leading to the creation of security standards and best practices to mitigate these risks. In 2000, the term ‘Cross-Site Scripting’ was formalized in the cybersecurity community, and since then it has been a focal point in web vulnerability research.
Uses: XSS is primarily used to steal sensitive user information, such as login credentials and personal data. It can also be employed for phishing attacks, redirecting users to malicious sites, or spreading malware. Attackers can exploit XSS vulnerabilities to execute scripts that alter the appearance of a website or perform actions on behalf of the user without their consent.
Examples: An example of reflected XSS is when a user clicks on a malicious link that includes a script in the URL, causing the browser to execute the script and steal their information. A case of stored XSS can be observed in forums where an attacker posts a comment containing a malicious script, which then executes in the browsers of other users visiting the page. Another example is DOM-based XSS, where the script executes as a result of manipulating the browser’s Document Object Model (DOM).
