Security Glossary

Certificate Pinning Bypass

Techniques to circumvent certificate pinning in mobile apps, allowing HTTPS traffic interception for security testing or malicious purposes.

Certificate Pinning Bypass refers to techniques used to circumvent certificate pinning protections in mobile apps or clients, allowing man-in-the-middle interception of HTTPS traffic for security testing or malicious purposes.

What is Certificate Pinning?

Certificate pinning is a security measure where applications only trust specific certificates or public keys, rather than any certificate signed by a trusted CA. This prevents MITM attacks even if an attacker has a valid CA-signed certificate.

Common Bypass Techniques

Runtime Instrumentation (Frida)

// Frida script to bypass pinning
Java.perform(function() {
    var TrustManager = Java.use('javax.net.ssl.X509TrustManager');
    TrustManager.checkServerTrusted.implementation = function() {
        return;  // Accept all certificates
    };
});

Tools for Bypassing

  • Frida: Dynamic instrumentation toolkit
  • Objection: Runtime mobile exploration
  • SSLUnpinning: Xposed/Magisk modules
  • apk-mitm: Automated APK patching

Binary Patching

  • Modify the app binary to remove pinning checks
  • Replace pinned certificates with attacker's certificate
  • Disable certificate validation functions

Legitimate Use Cases

  • Security testing of mobile applications
  • Debugging network traffic during development
  • Security research and vulnerability assessment

See Also