diff --git a/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java b/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java
index 8dbcc00..310d7bf 100644
--- a/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java
+++ b/tests/cts/net/src/android/net/cts/ConnectivityManagerTest.java
@@ -2751,6 +2751,27 @@
                 mCm.getActiveNetwork(), false /* accept */ , false /* always */));
     }
 
+    private void ensureCellIsValidatedBeforeMockingValidationUrls() {
+        // Verify that current supported network is validated so that the mock http server will not
+        // apply to unexpected networks. Also see aosp/2208680.
+        //
+        // This may also apply to wifi in principle, but in practice methods that mock validation
+        // URL all disconnect wifi forcefully anyway, so don't wait for wifi to validate.
+        if (mPackageManager.hasSystemFeature(FEATURE_TELEPHONY)) {
+            ensureValidatedNetwork(makeCellNetworkRequest());
+        }
+    }
+
+    private void ensureValidatedNetwork(NetworkRequest request) {
+        final TestableNetworkCallback cb = new TestableNetworkCallback();
+        mCm.registerNetworkCallback(request, cb);
+        cb.eventuallyExpect(CallbackEntry.NETWORK_CAPS_UPDATED,
+                NETWORK_CALLBACK_TIMEOUT_MS,
+                entry -> ((CallbackEntry.CapabilitiesChanged) entry).getCaps()
+                        .hasCapability(NET_CAPABILITY_VALIDATED));
+        mCm.unregisterNetworkCallback(cb);
+    }
+
     @AppModeFull(reason = "WRITE_DEVICE_CONFIG permission can't be granted to instant apps")
     @Test
     public void testAcceptPartialConnectivity_validatedNetwork() throws Exception {
@@ -2882,7 +2903,8 @@
             assertTrue(mCm.getNetworkCapabilities(wifiNetwork).hasCapability(
                     NET_CAPABILITY_VALIDATED));
 
-            // Configure response code for unvalidated network
+            // The cell network has already been checked to be validated.
+            // Configure response code for unvalidated network.
             configTestServer(Status.INTERNAL_ERROR, Status.INTERNAL_ERROR);
             mCm.reportNetworkConnectivity(wifiNetwork, false);
             // Default network should stay on unvalidated wifi because avoid bad wifi is disabled.
@@ -2970,6 +2992,8 @@
     }
 
     private Network prepareValidatedNetwork() throws Exception {
+        ensureCellIsValidatedBeforeMockingValidationUrls();
+
         prepareHttpServer();
         configTestServer(Status.NO_CONTENT, Status.NO_CONTENT);
         // Disconnect wifi first then start wifi network with configuration.
@@ -2980,6 +3004,8 @@
     }
 
     private Network preparePartialConnectivity() throws Exception {
+        ensureCellIsValidatedBeforeMockingValidationUrls();
+
         prepareHttpServer();
         // Configure response code for partial connectivity
         configTestServer(Status.INTERNAL_ERROR  /* httpsStatusCode */,
@@ -2993,6 +3019,8 @@
     }
 
     private Network prepareUnvalidatedNetwork() throws Exception {
+        ensureCellIsValidatedBeforeMockingValidationUrls();
+
         prepareHttpServer();
         // Configure response code for unvalidated network
         configTestServer(Status.INTERNAL_ERROR /* httpsStatusCode */,