Application vulnerabilities can turn the app itself into an attack vector, enabling attackers to compromise users’ systems and data through malware delivery, code injection, or unauthorized data exfiltration.

Scenario: Alice's application abuse

Alize leverages vulnerabilities in the application to compromise the systems, data, or security of users who interact with it. This could include malicious downloads, code injection in content delivered to users, or manipulating application responses to compromise user devices.

Threat Modeling

STRIDE

Primary impact depends on the impact of attack:

1. Malware delivery could be Tampering or DoS.
2. Phishing / impersonation: Could be Spoofing or Information Disclosure.
3. Data exfiltration could be Information Disclosure.

What can go wrong?

Consider how the application's normal functionality might be used to the disbenefit of an another application, of some or all users, of another party, or even of society. This may include:

1. Performing denial of service.
2. Hosting/distribution of unapproved content (e.g. videos, photos, malware).
3. Generating of spam messages.
4. Hosting unapproved application code (e.g. as a command and control server, or as a bot).
5. Reflecting an attack against another system.
6. Attacking another internal system (e.g. databases, internal network).

Considering these threats, the impact could be that:

1. Users’ devices get infected with malware, ransomware, or spyware.
2. Sensitive personal or financial data is stolen.
3. Users are tricked into revealing credentials or performing harmful actions.
4. Reputational damage for the application provider.
5. Legal and regulatory consequences if user harm is significant.
6. Reputational damage for the application provider.
7. Legal and regulatory consequences if user harm is significant.

What are we going to do about it?

1. Input and Output Validation: Sanitize all data sent to users to prevent injection attacks (e.g., XSS, malicious file downloads).
2. Content Security Policies (CSP): Restrict what can run or be loaded in users’ browsers.
3. Secure Third-Party Dependencies: Ensure libraries and frameworks are patched and trusted.
4. User Education: Warn users about suspicious activity and encourage secure practices.
5. Monitoring and Incident Response: Detect and respond to attacks leveraging your application quickly.
6. Least Privilege & Sandboxing: Limit the capability of the application to affect client systems beyond its scope.