Client Side Vulnerabilities / Insecure Data Process in DOM
Insecure data process in DOM, also known as CWE-20, is a vulnerability that exists in web and API applications where user input data is processed and stored without proper validation or protection. This type of vulnerability can lead to a variety of security issues, such as Cross-Site Scripting (XSS), SQL injection, and more. The OWASP Testing Guide provides guidance on how to identify and address this type of vulnerability. (CWE Directory, n.d.; OWASP, n.d.).
Insecure data process in DOM is a high-risk vulnerability as it can give attackers access to sensitive data, such as passwords, financial information, and personal data. It also allows attackers to bypass authentication and authorization mechanisms, leading to data theft, data manipulation, and other malicious activities.
The best way to prevent this type of vulnerability is to use a combination of client-side and server-side validation to ensure that any user input is properly checked before being accepted and processed. In addition, all data should be encrypted and stored securely.
The following example from CVE-2020-7794 shows how an attacker can use an insecure data process in DOM to inject malicious code into an application:
<script> var userData = document.getElementById("user-data").value; // No validation or escaping document.write(userData); </script>
This code allows an attacker to inject malicious code into the application without any validation or escaping.