What mobile app security vulnerabilities should you test for?

2 Weak encryption

Another mobile app security vulnerability is weak encryption. Encryption is a technique to transform data into an unreadable format using a secret key, so that only authorized parties can decrypt it. However, encryption can be weak if the key is too short, predictable, or hard-coded in the app, or if the algorithm is outdated, flawed, or misconfigured. For example, an attacker can use a brute-force attack to guess the key, or use a reverse engineering tool to extract the key from the app's binary. To test for weak encryption, you can use tools like Frida, Radare2, or APKTool to inspect the app's encryption methods, keys, and libraries. You can also use dynamic analysis tools like Burp Suite or Wireshark to capture and decrypt the app's network traffic.

3 Broken authentication

A third mobile app security vulnerability is broken authentication. Authentication is a process to verify the identity of a user or a device before granting access to the app's resources or functions. However, authentication can be broken if the app does not implement strong passwords, multi-factor authentication, session management, or device binding. For example, an attacker can use a phishing attack to obtain the user's credentials, or use a session hijacking attack to take over the user's session. To test for broken authentication, you can use tools like Metasploit, Nmap, or Hydra to scan the app's ports, services, or protocols. You can also use manual testing techniques like password guessing, credential stuffing, or session replaying to bypass the app's authentication mechanisms.

4 Insufficient input validation

A fourth mobile app security vulnerability is insufficient input validation. Input validation is a technique to check the validity and integrity of the data that the app receives from the user, the device, or the network. However, input validation can be insufficient if the app does not filter, sanitize, or reject malicious or unexpected data. For example, an attacker can use a SQL injection attack to execute arbitrary commands on the app's database, or use a buffer overflow attack to overwrite the app's memory. To test for insufficient input validation, you can use tools like SQLMap, ZAP, or Nuclei to inject malicious data into the app's inputs, such as text fields, URLs, or headers. You can also use fuzzing tools like AFL, Peach, or Radamsa to generate random or malformed data and observe the app's behavior.

5 Improper error handling

A fifth mobile app security vulnerability is improper error handling. Error handling is a technique to handle and respond to errors or exceptions that occur during the app's execution. However, error handling can be improper if the app does not catch, log, or report errors properly, or if it exposes too much information or functionality in the error messages. For example, an attacker can use a denial-of-service attack to crash the app, or use a debug tool to exploit the app's error logs or stack traces. To test for improper error handling, you can use tools like Crashlytics, Sentry, or Logcat to monitor and analyze the app's errors, logs, or crashes. You can also use manual testing techniques like invalid inputs, network interruptions, or resource exhaustion to trigger and examine the app's error responses.

6 Insecure communication

A sixth mobile app security vulnerability is insecure communication. Communication is a technique to exchange data between the app and the server, the device, or other apps. However, communication can be insecure if the app does not use secure protocols, certificates, or encryption to protect the data in transit. For example, an attacker can use a man-in-the-middle attack to intercept, modify, or redirect the app's communication, or use a SSL stripping attack to downgrade the app's communication from HTTPS to HTTP. To test for insecure communication, you can use tools like SSLyze, TestSSL, or SSL Labs to assess the app's SSL/TLS configuration, certificates, and vulnerabilities. You can also use proxy tools like Charles, Fiddler, or Mitmproxy to inspect and manipulate the app's communication.