Info Obfuscated methods

Description

Obfuscation refers to methods to obscure code and make it hard to understand. Compiled Java classes can be decompiled if there is no obfuscation during compilation step.

Adversaries can steal code and repurpose it and sell it in a new application or create a malicious fake application based on the initial one.

Code obfuscation only slows the attacker from reverse engineering but does not make it impossible.

Recommendation

Design the application to add the following protections and slow reverse engineering of the application:

  • Obfuscate Java source code with tools like Proguard or Dexguard
  • buildTypes {
            release {
                minifyEnabled true
                proguardFiles getDefaultProguardFile('proguard-android.txt'),
                'proguard-rules.pro'
            }
        }
  • Verification application signing certificate during runtime by checking context.getPackageManager().signature
  • Check application installer to ensure it matches the Android Market by calling context.getPackageManager().getInstallerPackageName
  • Check running environment at runtime
  • private static String getSystemProperty(String name) throws Exception {
        Class systemPropertyClazz = Class.forName("android.os.SystemProperties");
        return (String) systemPropertyClazz.getMethod("get", new Class[] { String.class }).invoke(systemPropertyClazz, new Object[] { name });
    }
    
    public static boolean checkEmulator() {
    
        try {
            boolean goldfish = getSystemProperty("ro.hardware").contains("goldfish");
            boolean qemu = getSystemProperty("ro.kernel.qemu").length() > 0;
            boolean sdk = getSystemProperty("ro.product.model").equals("sdk");
    
            if (qemu || goldfish || sdk) {
                return true;
            }
    
        } catch (Exception e) {
        }
    
        return false;
      }
  • Check debug flag at runtime
  • context.getApplicationInfo().applicationInfo.flags & ApplicationInfo.FLAG_DEBUGGABLE;

Technical details
PackageObfuscated
com.deniz.business False
com.nineoldandroids.view False
org.java_websocket False
com.facebook False
android.support.v4 False
com.jcmore2.shakeit False
com.google.zxing False
com.deniz.firebase False
com.szugyi.circlemenu False
android.support.annotation False
com.deniz.messaging False
com.daimajia.swipe False
com.squareup.picasso False
com.deniz.views False
android.support.design False
com.lukedeighton.wheelview False
com.viewpagerindicator False
com.google.gson False
com.scottyab.showhidepasswordedittext False
com.denizbank.dijitaldeniz False
com.nineoldandroids.animation False
com.google.ads False
bolts False
com.google.firebase True
com.journeyapps.barcodescanner False
com.deniz.dijitaldeniz False
net.hockeyapp.android False
android.support.multidex False
cn.pedant.SweetAlert False
com.makeramen.roundedimageview False
com.nineoldandroids.util False
com.android.volley False
com.crashlytics.android False