Mobile Ssl Pinning Bypass

# SKILL: Mobile SSL Pinning Bypass — Expert Attack Playbook

> **AI LOAD INSTRUCTION**: Expert SSL pinning bypass techniques for mobile platforms. Covers Android and iOS bypass methods (Frida, Objection, Xposed, SSL Kill Switch), framework-specific bypasses (Flutter, React Native, Xamarin), and troubleshooting non-standard pinning implementations. Base models miss framework-specific hook points and multi-layer pinning configurations.

## 0. RELATED ROUTING

Before going deep, consider loading:

- [android-pentesting-tricks](../android-pentesting-tricks/SKILL.md) for broader Android testing beyond SSL bypass
- [ios-pentesting-tricks](../ios-pentesting-tricks/SKILL.md) for broader iOS testing beyond SSL bypass
- [api-sec](../api-sec/SKILL.md) once traffic is intercepted for API-level testing

---

## 1. SSL PINNING TYPES

| Pinning Type | What Is Pinned | Resilience | Common In |
|---|---|---|---|
| Certificate pinning | Exact leaf certificate (DER/PEM) | Low (breaks on cert rotation) | Legacy apps |
| Public key pinning | Subject Public Key Info | Medium (survives cert renewal if key unchanged) | Modern apps |
| SPKI hash pinning | SHA-256 of SPKI | Medium (same as public key) | OkHttp, AFNetworking |
| CA pinning | Intermediate or root CA cert | High (any cert from that CA works) | Enterprise apps |
| Multi-pin (backup pins) | Primary + backup pins | High (fallback pins) | HPKP-aware apps |

### How Pinning Works

```
TLS Handshake
│
├── Server presents certificate chain
│
├── Standard validation (system trust store)
│   └── Passes? continue : connection fails
│
└── Pin validation (app-level check)
    ├── Extract server cert/pubkey/SPKI hash
    ├── Compare against embedded pins
    └── Match found? → allow : → reject connection
```

---

## 2. ANDROID BYPASS METHODS

### 2.1 Frida Universal SSL Bypass

```javascript
// Hooks TrustManager, OkHttp, Volley, Retrofit, Conscrypt
Java.perform(function() {

    // ── TrustManagerImpl (Android system) ──
    try {
        var TMI = Java.use('com.android.org.conscrypt.TrustManagerImpl');
        TMI.verifyChain.implementation = function() {
            console.log('[Bypass] TrustManagerImpl.verifyChain');
            return arguments[0]; // return untouched chain
        };
    } catch(e) {}

    // ── X509TrustManager (custom implementations) ──
    var TrustManager = Java.registerClass({
        name: 'com.bypass.TrustManager',
        implements: [Java.use('javax.net.ssl.X509TrustManager')],
        methods: {
            checkClientTrusted: function() {},
            checkServerTrusted: function() {},
            getAcceptedIssuers: function() { return []; }
        }
    });

    var SSLContext = Java.use('javax.net.ssl.SSLContext');
    SSLContext.init.overload('[Ljavax.net.ssl.KeyManager;',
        '[Ljavax.net.ssl.TrustManager;', 'java.security.SecureRandom')
        .implementation = function(km, tm, sr) {
        console.log('[Bypass] SSLContext.init');
        this.init(km, [TrustManager.$new()], sr);
    };

    // ── OkHttp3 CertificatePinner ──
    try {
        var CP = Java.use('okhttp3.CertificatePinner');
        CP.check.overload('java.lang.String', 'java.util.List').implementation = function() {
            console.log('[Bypass] OkHttp3 CertificatePinner.check: ' + arguments[0]);
        };
        // check$okhttp variant (OkHttp 4.x)
        try { CP['check$okhttp'].implementation = function() {}; } catch(e) {}
    } catch(e) {}

    // ── Retrofit / OkHttp interceptor ──
    try {
        var OkHttpClient = Java.use('okhttp3.OkHttpClient$Builder');
        OkHttpClient.certificatePinner.implementation = function(pinner) {
            console.log('[Bypass] Ok