Sorted!! Play store: Remediation for Intent Redirection Vulnerability for Flutter - flutter

Question

I have a question with regards to how to remedy intent redirection. I am not extremely well versed in Android, as the solutions offered on the Google Support page doesn't seem to address for flutter applications. I have noted that the question was asked before but wasn't explanatory
I have spent the last couple of days looking for a solution but each attempted solution on the support page fails when I reupload it to the play store. I've also contacted Google Support and they have validated that the vulnerability is still present.
Any help would be greatly appreciated thanks.
Some of the solution I have tried are:
1.
import io.flutter.embedding.android.FlutterActivity
import io.flutter.embedding.engine.FlutterEngine
import android.content.Intent
import android.os.Bundle
import androidx.annotation.RequiresApi
class MainActivity: FlutterActivity() {
#RequiresApi(Build.VERSION_CODES.O)
override fun configureFlutterEngine(#NonNull flutterEngine: FlutterEngine) {
super.configureFlutterEngine(flutterEngine)
if (callingActivity?.packageName.equals("known")) {
// val _intent = intent;
// // extract the nested Intent
// val forward:Intent = _intent.getParcelableExtra("key")
// // redirect the nested Intent
val _intent = intent;
// remove the grant URI permissions in the untrusted Intent
_intent.removeFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
_intent.removeFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
// extract the nested Intent
var forward :Intent = _intent.getParcelableExtra("Key")!!
startActivity(forward);
}
// startActivity(_intent)
}
}
Setting android:export = false, crashes the app
<activity
android:name=".MainActivity"
android:exported="false"
android:launchMode="singleTop"
android:theme="#style/LaunchTheme"
android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
android:hardwareAccelerated="true"
android:windowSoftInputMode="adjustResize">
<!-- Specifies an Android theme to apply to this Activity as soon as
the Android process has started. This theme is visible to the user
while the Flutter UI initializes. After that, this theme continues
to determine the Window background behind the Flutter UI. -->
<meta-data
android:name="io.flutter.embedding.android.NormalTheme"
android:resource="#style/NormalTheme"
/>
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
<intent-filter>
<action android:name="RECEIVE_DEFAULT" />
<category android:name="android.intent.category.DEFAULT"/>
</intent-filter>
</activity>
Edit:
I found the solution.
So [after reading carefully about intent vulnerability][1] I understood where my error was. The link above explains clearly on how untrusted intents can be used to exploit your application and access protected files. Google play tests your app bundle for this vulnerability by "intent injection". So removing the read and write flags from the intent helps prevent unauthorised access.
override fun onCreate(savedInstanceState: Bundle?) {
intent?.removeFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
intent?.removeFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
super.onCreate(savedInstanceState)
}
This thus makes the intent "safe". I hope this helps everyone who encounters this issue. Happy coding
[1]: What is an Android PendingIntent?