Authorization / Android Class Loading Hijacking

Description

Android Class Loading Hijacking (CWE-919) is a vulnerability that affects the authorization process in Android and mobile app development. It is a type of vulnerability in which an attacker is able to exploit an application's class loading procedure to inject malicious code into the application. This malicious code can then be used to gain access to restricted resources within the application, such as private user data or system settings. According to the Common Weakness Enumeration (CWE) directory, this vulnerability is a weakness in authorization, specifically related to improper input validation and privilege escalation. Additionally, the OWASP Testing Guide lists this vulnerability as a high-risk vulnerability due to its potential for exploitation.

Risk

Android Class Loading Hijacking poses a significant risk to applications, as it can allow an attacker to bypass authentication and authorization checks to gain access to restricted resources. Additionally, attackers may be able to use an application’s class loading procedure to inject malicious code or malware that can be used to gain access to a user’s credentials or other sensitive data.

Solution

Android Class Loading Hijacking can be prevented by properly validating user input and implementing secure authorization procedures. Additionally, developers should ensure that the class loading procedure is secure, as attackers may be able to exploit insecure class loading to inject malicious code. Developers should also ensure that any application-level resources are properly secured and that authorization checks are properly implemented.

Example

The following example shows how an attacker can use Android Class Loading Hijacking to gain access to a user’s credentials.

public class MyClass{
    public static void main(String[] args){
        // attacker can hijack class loading process to inject malicious code
        Class.forName("com.attacker.MyMaliciousCode");
        // attacker can use the malicious code to gain access to user's credentials
        String username = getUsername();
        String password = getPassword();
    }
}