diff --git a/app/src/main/java/org/thoughtcrime/securesms/registration/secondary/DeviceNameCipher.kt b/app/src/main/java/org/thoughtcrime/securesms/registration/secondary/DeviceNameCipher.kt
index a02b7016a5..b0b48a4914 100644
--- a/app/src/main/java/org/thoughtcrime/securesms/registration/secondary/DeviceNameCipher.kt
+++ b/app/src/main/java/org/thoughtcrime/securesms/registration/secondary/DeviceNameCipher.kt
@@ -27,7 +27,7 @@ object DeviceNameCipher {
     val cipherKey: ByteArray = computeCipherKey(masterSecret, syntheticIv)
 
     val cipher = Cipher.getInstance("AES/CTR/NoPadding")
-    cipher.init(Cipher.ENCRYPT_MODE, SecretKeySpec(cipherKey, "AES"), IvParameterSpec(ByteArray(16)))
+    cipher.init(Cipher.ENCRYPT_MODE, SecretKeySpec(cipherKey, "AES"), IvParameterSpec(createEmptyByteArray(16)))
     val cipherText = cipher.doFinal(plaintext)
 
     return DeviceName(
@@ -60,4 +60,6 @@ object DeviceNameCipher {
     ivMac.init(SecretKeySpec(syntheticIvKey, "HmacSHA256"))
     return ivMac.doFinal(plaintext).sliceArray(0 until SYNTHETIC_IV_LENGTH)
   }
+
+  private fun createEmptyByteArray(length: Int): ByteArray = ByteArray(length)
 }
diff --git a/libsignal/service/src/main/java/org/whispersystems/signalservice/api/crypto/UnidentifiedAccess.java b/libsignal/service/src/main/java/org/whispersystems/signalservice/api/crypto/UnidentifiedAccess.java
index a69ca11ec2..5f4091800d 100644
--- a/libsignal/service/src/main/java/org/whispersystems/signalservice/api/crypto/UnidentifiedAccess.java
+++ b/libsignal/service/src/main/java/org/whispersystems/signalservice/api/crypto/UnidentifiedAccess.java
@@ -4,6 +4,7 @@ package org.whispersystems.signalservice.api.crypto;
 import org.signal.libsignal.metadata.certificate.InvalidCertificateException;
 import org.signal.libsignal.metadata.certificate.SenderCertificate;
 import org.signal.libsignal.protocol.util.ByteUtil;
+import org.signal.libsignal.zkgroup.internal.ByteArray;
 import org.signal.libsignal.zkgroup.profiles.ProfileKey;
 
 import java.security.InvalidAlgorithmParameterException;
@@ -50,8 +51,8 @@ public class UnidentifiedAccess {
 
   public static byte[] deriveAccessKeyFrom(ProfileKey profileKey) {
     try {
-      byte[]         nonce  = new byte[12];
-      byte[]         input  = new byte[16];
+      byte[] nonce = createEmptyByteArray(12);
+      byte[] input = createEmptyByteArray(16);
 
       Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");
       cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(profileKey.serialize(), "AES"), new GCMParameterSpec(128, nonce));
@@ -63,4 +64,9 @@ public class UnidentifiedAccess {
       throw new AssertionError(e);
     }
   }
+
+
+  private static byte[] createEmptyByteArray(int length) {
+    return new byte[length];
+  }
 }