diff --git a/framework-t/src/android/net/NetworkIdentity.java b/framework-t/src/android/net/NetworkIdentity.java
index edfd21c..947a092 100644
--- a/framework-t/src/android/net/NetworkIdentity.java
+++ b/framework-t/src/android/net/NetworkIdentity.java
@@ -32,6 +32,7 @@
 import android.net.wifi.WifiInfo;
 import android.service.NetworkIdentityProto;
 import android.telephony.TelephonyManager;
+import android.util.Log;
 import android.util.proto.ProtoOutputStream;
 
 import com.android.net.module.util.BitUtils;
@@ -406,10 +407,18 @@
             setOemManaged(getOemBitfield(snapshot.getNetworkCapabilities()));
 
             if (mType == TYPE_WIFI) {
-                final TransportInfo transportInfo = snapshot.getNetworkCapabilities()
-                        .getTransportInfo();
+                final NetworkCapabilities nc = snapshot.getNetworkCapabilities();
+                final TransportInfo transportInfo = nc.getTransportInfo();
                 if (transportInfo instanceof WifiInfo) {
                     final WifiInfo info = (WifiInfo) transportInfo;
+                    // Log.wtf to catch trying to set a null wifiNetworkKey into NetworkIdentity.
+                    // See b/266598304. The problematic data that has null wifi network key is
+                    // thrown out when storing data, which is handled by the service.
+                    if (info.getNetworkKey() == null) {
+                        Log.wtf(TAG, "WifiInfo contains a null wifiNetworkKey and it will"
+                                + " be set into NetworkIdentity, netId=" + snapshot.getNetwork()
+                                + "NetworkCapabilities=" + nc);
+                    }
                     setWifiNetworkKey(info.getNetworkKey());
                 }
             } else if (mType == TYPE_TEST) {
diff --git a/framework-t/src/android/net/NetworkTemplate.java b/framework-t/src/android/net/NetworkTemplate.java
index 55fcc4a..d90bd8d 100644
--- a/framework-t/src/android/net/NetworkTemplate.java
+++ b/framework-t/src/android/net/NetworkTemplate.java
@@ -700,7 +700,15 @@
      *                  to know details about the key.
      */
     private boolean matchesWifiNetworkKey(@NonNull String wifiNetworkKey) {
-        Objects.requireNonNull(wifiNetworkKey);
+        // Note that this code accepts null wifi network keys because of a past bug where wifi
+        // code was sending a null network key for some connected networks, which isn't expected
+        // and ended up stored in the data on many devices.
+        // A null network key in the data matches a wildcard template (one where
+        // {@code mMatchWifiNetworkKeys} is empty), but not one where {@code MatchWifiNetworkKeys}
+        // contains null. See b/266598304.
+        if (wifiNetworkKey == null) {
+            return CollectionUtils.isEmpty(mMatchWifiNetworkKeys);
+        }
         return CollectionUtils.isEmpty(mMatchWifiNetworkKeys)
                 || CollectionUtils.contains(mMatchWifiNetworkKeys, wifiNetworkKey);
     }
diff --git a/service-t/src/com/android/server/net/NetworkStatsService.java b/service-t/src/com/android/server/net/NetworkStatsService.java
index 9176ec2..ee7044a 100644
--- a/service-t/src/com/android/server/net/NetworkStatsService.java
+++ b/service-t/src/com/android/server/net/NetworkStatsService.java
@@ -106,6 +106,7 @@
 import android.net.TetherStatsParcel;
 import android.net.TetheringManager;
 import android.net.TrafficStats;
+import android.net.TransportInfo;
 import android.net.UnderlyingNetworkInfo;
 import android.net.Uri;
 import android.net.netstats.IUsageCallback;
@@ -113,6 +114,7 @@
 import android.net.netstats.provider.INetworkStatsProvider;
 import android.net.netstats.provider.INetworkStatsProviderCallback;
 import android.net.netstats.provider.NetworkStatsProvider;
+import android.net.wifi.WifiInfo;
 import android.os.Binder;
 import android.os.Build;
 import android.os.Bundle;
@@ -2125,6 +2127,14 @@
             final NetworkIdentity ident = NetworkIdentity.buildNetworkIdentity(mContext, snapshot,
                     isDefault, ratType);
 
+            // If WifiInfo contains a null network key then this identity should not be added into
+            // the network identity set. See b/266598304.
+            final TransportInfo transportInfo = snapshot.getNetworkCapabilities()
+                    .getTransportInfo();
+            if (transportInfo instanceof WifiInfo) {
+                final WifiInfo info = (WifiInfo) transportInfo;
+                if (info.getNetworkKey() == null) continue;
+            }
             // Traffic occurring on the base interface is always counted for
             // both total usage and UID details.
             final String baseIface = snapshot.getLinkProperties().getInterfaceName();
diff --git a/tests/unit/java/android/net/NetworkTemplateTest.kt b/tests/unit/java/android/net/NetworkTemplateTest.kt
index edbcea9..fc25fd8 100644
--- a/tests/unit/java/android/net/NetworkTemplateTest.kt
+++ b/tests/unit/java/android/net/NetworkTemplateTest.kt
@@ -130,10 +130,17 @@
                 mockContext, buildWifiNetworkState(null, TEST_WIFI_KEY1), true, 0)
         val identWifiImsi1Key1 = buildNetworkIdentity(
                 mockContext, buildWifiNetworkState(TEST_IMSI1, TEST_WIFI_KEY1), true, 0)
+        // This identity with a null wifiNetworkKey is to test matchesWifiNetworkKey won't crash
+        // the system when a null wifiNetworkKey is provided, which happens because of a bug in wifi
+        // and it should still match the wifi wildcard template. See b/266598304.
+        val identWifiNullKey = buildNetworkIdentity(
+                mockContext, buildWifiNetworkState(null /* subscriberId */,
+                null /* wifiNetworkKey */), true, 0)
 
         templateWifiWildcard.assertDoesNotMatch(identMobileImsi1)
         templateWifiWildcard.assertMatches(identWifiImsiNullKey1)
         templateWifiWildcard.assertMatches(identWifiImsi1Key1)
+        templateWifiWildcard.assertMatches(identWifiNullKey)
     }
 
     @Test
@@ -148,6 +155,9 @@
                 .setWifiNetworkKeys(setOf(TEST_WIFI_KEY1)).build()
         val templateWifiKeyAllImsi1 = NetworkTemplate.Builder(MATCH_WIFI)
                 .setSubscriberIds(setOf(TEST_IMSI1)).build()
+        val templateNullWifiKey = NetworkTemplate(MATCH_WIFI,
+                emptyArray<String>() /* subscriberIds */, arrayOf(null) /* wifiNetworkKeys */,
+                METERED_ALL, ROAMING_ALL, DEFAULT_NETWORK_ALL, NETWORK_TYPE_ALL, OEM_MANAGED_ALL)
 
         val identMobile1 = buildNetworkIdentity(mockContext, buildMobileNetworkState(TEST_IMSI1),
                 false, TelephonyManager.NETWORK_TYPE_UMTS)
@@ -159,6 +169,12 @@
                 mockContext, buildWifiNetworkState(TEST_IMSI2, TEST_WIFI_KEY1), true, 0)
         val identWifiImsi1Key2 = buildNetworkIdentity(
                 mockContext, buildWifiNetworkState(TEST_IMSI1, TEST_WIFI_KEY2), true, 0)
+        // This identity with a null wifiNetworkKey is to test the matchesWifiNetworkKey won't crash
+        // the system when a null wifiNetworkKey is provided, which would happen in some unknown
+        // cases, see b/266598304.
+        val identWifiNullKey = buildNetworkIdentity(
+                mockContext, buildWifiNetworkState(null /* subscriberId */,
+                null /* wifiNetworkKey */), true, 0)
 
         // Verify that template with WiFi Network Key only matches any subscriberId and
         // specific WiFi Network Key.
@@ -191,6 +207,12 @@
         templateWifiKeyAllImsi1.assertMatches(identWifiImsi1Key1)
         templateWifiKeyAllImsi1.assertDoesNotMatch(identWifiImsi2Key1)
         templateWifiKeyAllImsi1.assertMatches(identWifiImsi1Key2)
+
+        // Test a network identity with null wifiNetworkKey won't crash.
+        // It should not match a template with wifiNetworkKeys is non-null.
+        // Also, it should not match a template with wifiNetworkKeys that contains null.
+        templateWifiKey1.assertDoesNotMatch(identWifiNullKey)
+        templateNullWifiKey.assertDoesNotMatch(identWifiNullKey)
     }
 
     @Test