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
me.leolin.shortcutbadger True
android.support.c True
com.korvac.liquid True
com.squareup.picasso True
com.c.a True
com.google.gson True
org.greenrobot.eventbus True
com.crashlytics.android False
b True
okhttp3 True
android.support.design True
com.google.zxing True
pl.droidsonroids.gif True
com.baoyz.swipemenulistview True
com.bumptech.glide True
a.a True
retrofit2 False
com.facebook True
com.ifttt.sparklemotion True
android.support.a True
com.b.a True
com.pnikosis.materialishprogress True
com.splunk.mint True
cn.pedant.SweetAlert True
io.card.payment True
org.joda.time True
lolodev.permissionswrapper True
rx True
com.google.firebase True
com.dlazaro66.qrcodereaderview True
de.hdodenhof.circleimageview True
com.chauthai.swipereveallayout True
okio True
com.gu.toolargetool True
com.d.a True