[Bug]: Android SDK v5.x: Network requests to api.onesignal.com fail with UnknownHostException and Connection reset in the UAE

[midhlajnazar]

What happened?

When initializing onesignal_flutter (v5.5.2 / Android SDK 051002) on Android (both emulators and physical devices), OneSignal fails to fetch parameters or initialize because requests to https://api.onesignal.com consistently throw UnknownHostException and SocketException: Connection reset during the TLS handshake.

Steps to reproduce?

1.
Initialize onesignal_flutter (^5.5.2) in a Flutter application on Android using a valid OneSignal App ID:
Dart
OneSignal.initialize("YOUR_ONESIGNAL_APP_ID");
2.
Run the application on an Android emulator or a physical Android device connected to a standard network/cellular network in the UAE (using local ISPs like Etisalat or du) without a VPN enabled.
3.
Inspect Logcat logs during app startup.
4.
Observe that OneSignal's background worker attempts to fetch Android parameters (GET https://api.onesignal.com/apps/.../android_params.js) and immediately fails.
5.
Notice the resulting java.net.UnknownHostException and java.net.SocketException: Connection reset errors in the logs.

What did you expect to happen?

nslookup api.onesignal.com and curl requests to https://api.onesignal.com time out both on local Wi-Fi and mobile cellular data in the UAE

OneSignal Flutter SDK version

Plugin Version: onesignal_flutter: ^5.5.2 • Android SDK Version: 051002 (Flutter wrapper 050612) • Platform: Android (Emulator & Physical Devices) • Region/Network: United Arab Emirates (UAE) - ISPs (Etisalat / du)

Which platform(s) are affected?

• iOS
• Android

Relevant log output

W/OneSignal(31479): [OneSignal-IO-2] HttpClient: null Error thrown from network stack. 
W/OneSignal(31479): java.net.SocketException: Connection reset
W/OneSignal(31479): 	at java.net.SocketInputStream.read(SocketInputStream.java:191)
W/OneSignal(31479): 	at java.net.SocketInputStream.read(SocketInputStream.java:143)
W/OneSignal(31479): 	at com.android.org.conscrypt.ConscryptEngineSocket$SSLInputStream.readFromSocket(ConscryptEngineSocket.java:1015)
W/OneSignal(31479): 	at com.android.org.conscrypt.ConscryptEngineSocket$SSLInputStream.processDataFromSocket(ConscryptEngineSocket.java:979)
W/OneSignal(31479): 	at com.android.org.conscrypt.ConscryptEngineSocket$SSLInputStream.-$$Nest$mprocessDataFromSocket(ConscryptEngineSocket.java:0)
W/OneSignal(31479): 	at com.android.org.conscrypt.ConscryptEngineSocket.doHandshake(ConscryptEngineSocket.java:244)
W/OneSignal(31479): 	at com.android.org.conscrypt.ConscryptEngineSocket.startHandshake(ConscryptEngineSocket.java:226)
W/OneSignal(31479): 	at com.android.okhttp.internal.io.RealConnection.connectTls(RealConnection.java:194)
W/OneSignal(31479): 	at com.android.okhttp.internal.io.RealConnection.connectSocket(RealConnection.java:151)
W/OneSignal(31479): 	at com.android.okhttp.internal.io.RealConnection.connect(RealConnection.java:114)
W/OneSignal(31479): 	at com.android.okhttp.internal.http.StreamAllocation.findConnection(StreamAllocation.java:186)
W/OneSignal(31479): 	at com.android.okhttp.internal.http.StreamAllocation.findHealthyConnection(StreamAllocation.java:128)
W/OneSignal(31479): 	at com.android.okhttp.internal.http.StreamAllocation.newStream(StreamAllocation.java:97)
W/OneSignal(31479): 	at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:289)
W/OneSignal(31479): 	at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:232)
W/OneSignal(31479): 	at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:465)
W/OneSignal(31479): 	at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:411)
W/OneSignal(31479): 	at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java:542)
W/OneSignal(31479): 	at com.android.okhttp.internal.huc.DelegatingHttpsURLConnection.getResponseCode(DelegatingHttpsURLConnection.java:106)
W/OneSignal(31479): 	at com.android.okhttp.internal.huc.HttpsURLConnectionImpl.getResponseCode(HttpsURLConnectionImpl.java:27)
W/OneSignal(31479): 	at com.onesignal.core.internal.http.impl.HttpClient$makeRequestIODispatcher$job$1.invokeSuspend(HttpClient.kt:217)
W/OneSignal(31479): 	at com.onesignal.core.internal.http.impl.HttpClient$makeRequestIODispatcher$job$1.invoke(HttpClient.kt:8)
W/OneSignal(31479): 	at com.onesignal.core.internal.http.impl.HttpClient$makeRequestIODispatcher$job$1.invoke(HttpClient.kt:2)
W/OneSignal(31479): 	at com.onesignal.common.threading.ThreadUtilsKt$launchOnIO$1.invokeSuspend(ThreadUtils.kt:170)
W/OneSignal(31479): 	at com.onesignal.common.threading.ThreadUtilsKt$launchOnIO$1.invoke(ThreadUtils.kt:8)
W/OneSignal(31479): 	at com.onesignal.common.threading.ThreadUtilsKt$launchOnIO$1.invoke(ThreadUtils.kt:2)
W/OneSignal(31479): 	at com.onesignal.common.threading.OneSignalDispatchers$launchOnIO$1.invokeSuspend(OneSignalDispatchers.kt:202)
W/OneSignal(31479): 	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:34)
W/OneSignal(31479): 	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:101)
W/OneSignal(31479): 	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1100)
W/OneSignal(31479): 	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
W/OneSignal(31479): 	at java.lang.Thread.run(Thread.java:1571)
I/OneSignal(31479): [OneSignal-IO-2] Failed to get Android parameters, trying again in 90 seconds.
D/OneSignal(31479): [OneSignal-IO-2] FeatureFlagsBackendService.fetchRemoteFeatureFlags(appId=XXXX)
D/OneSignal(31479): [OneSignal-IO-1] HttpClient: Request Sent = GET https://api.onesignal.com/apps/XXXX/sdk/features/android/051002 - Body: null - Headers: Accept=[application/vnd.onesignal.v1+json], OneSignal-Fid-Env=[gs=0;agp=9.0.1;flag=0;reg=0;def=0;prov=1;min=24;tgt=36;snd=-], OneSignal-Install-Id=[XXXXX], OneSignal-Subscription-Id=[XXXX], SDK-Version=[onesignal/android/051002], SDK-Wrapper=[onesignal/flutter/050612]
I/OneSignal(31479): [OneSignal-IO-1] HttpClient: Could not send last request, device is offline. Throwable: java.net.UnknownHostException
D/OneSignal(31479): [OneSignal-IO-1] FeatureFlagsBackendService: non-success status=-1 body=<empty>

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[jfishman1]

Hi there,

Thank you for the report. This is a known issue and we're actively working on it.

What we know:

Since around September 18, connections to api.onesignal.com from inside the UAE are being blocked at the network level. It affects multiple UAE ISPs on both Wi-Fi and cellular. This is not caused by your app, your configuration, or the OneSignal SDK version, and nothing has changed on our side. Requests from outside the UAE work normally.

While the block is in place:

1. The OneSignal SDK on devices in the UAE cannot initialize, register subscriptions, or update users. You'll see errors like UnknownHostException, Connection reset, or TLS timeouts.
2. API requests sent from servers located in the UAE will time out.

What we're doing about it:

The UAE regulator (TDRA) has told affected customers the block was requested by the Ministry of Economy and Tourism. We've filed a formal request with the Ministry to review and lift it, and we're pursuing it through our regional partner and legal counsel in parallel. We don't have a timeline yet. Updates will be provided as soon as possible.

How you can help:

Requests from UAE businesses carry weight with local authorities. If you're able to, please:

1. Submit a review request to the Ministry of Economy and Tourism: https://www.moet.gov.ae/en/services. Explain that your business uses OneSignal (api.onesignal.com) to send notifications to your customers and that the block is disrupting your service.
2. If you have a UAE Pass, also file an unblock request with TDRA: https://tdra.gov.ae/en/Services/block-or-unblock-websites
3. If you're on du, report the block here: https://www.du.ae/surfsafely?ctype=unblock
4. Send us any reference number or reply you get back. It helps us push our own request forward.
5. If you haven't already, reply with your ISP and the approximate time the problem started for you.

We know this is disruptive and we're sorry for the impact on you and your users. We'll keep you posted!

[mustafasaify-glitch]

I am facing the same issue in the UAE on both iOS and Android. Despite users updating and launching the app multiple times, the OneSignal dashboard still shows older app versions and stale Last Session timestamps. Requests to api.onesignal.com are timing out, with DNS resolution sometimes taking around 100 seconds, followed by TLS connection timeouts.

[shehanargaam]

We are experiencing the same issue in the UAE.

Environment:

- `onesignal_flutter`: `5.6.x` / `5.7.0`
- Native OneSignal Android SDK: `051002`
- Flutter production app
- Android 16
- Device: Samsung Galaxy A55 5G (`SM-A556E`)
- Network: UAE Etisalat/du connections

The device notification permission is granted by Android, but OneSignal cannot create the subscription:

androidPermission=PermissionStatus.granted
oneSignalPermission=false
optedIn=false
subscriptionId=
hasToken=

We also see:

```text
NativePermissionController: checkPermission: missing 13

The same device previously worked with an older production release. The failure started after upgrading the OneSignal/native SDK versions.

From the UAE network, api.onesignal.com resolves through DNS, but HTTPS/TLS requests time out or reset. Because OneSignal cannot reach api.onesignal.com, the Android parameters and subscription registration do not complete.

Could you confirm whether there is an approved workaround for UAE networks, such as an alternate endpoint, regional routing, or proxy configuration? We can provide additional logs and test a patched SDK if needed.