diff --git a/monkey/monkey_island/cc/server_utils/encryption/data_store_encryptor.py b/monkey/monkey_island/cc/server_utils/encryption/data_store_encryptor.py
index 0af258d19..6b927e20b 100644
--- a/monkey/monkey_island/cc/server_utils/encryption/data_store_encryptor.py
+++ b/monkey/monkey_island/cc/server_utils/encryption/data_store_encryptor.py
@@ -46,10 +46,10 @@ class DataStoreEncryptor(IEncryptor):
 
         return KeyBasedEncryptor(plaintext_key)
 
-    def encrypt(self, plaintext: str) -> str:
+    def encrypt(self, plaintext: bytes) -> bytes:
         return self._key_based_encryptor.encrypt(plaintext)
 
-    def decrypt(self, ciphertext: str):
+    def decrypt(self, ciphertext: bytes) -> bytes:
         return self._key_based_encryptor.decrypt(ciphertext)
 
 
diff --git a/monkey/monkey_island/cc/server_utils/encryption/field_encryptors/string_encryptor.py b/monkey/monkey_island/cc/server_utils/encryption/field_encryptors/string_encryptor.py
index 28f0f2c93..6de6cb385 100644
--- a/monkey/monkey_island/cc/server_utils/encryption/field_encryptors/string_encryptor.py
+++ b/monkey/monkey_island/cc/server_utils/encryption/field_encryptors/string_encryptor.py
@@ -5,8 +5,8 @@ from . import IFieldEncryptor
 class StringEncryptor(IFieldEncryptor):
     @staticmethod
     def encrypt(value: str):
-        return get_datastore_encryptor().encrypt(value)
+        return get_datastore_encryptor().encrypt(value.encode())
 
     @staticmethod
     def decrypt(value: str):
-        return get_datastore_encryptor().decrypt(value)
+        return get_datastore_encryptor().decrypt(value).decode()
diff --git a/monkey/monkey_island/cc/server_utils/encryption/field_encryptors/string_list_encryptor.py b/monkey/monkey_island/cc/server_utils/encryption/field_encryptors/string_list_encryptor.py
index ce0ceb8dd..9adf733a4 100644
--- a/monkey/monkey_island/cc/server_utils/encryption/field_encryptors/string_list_encryptor.py
+++ b/monkey/monkey_island/cc/server_utils/encryption/field_encryptors/string_list_encryptor.py
@@ -7,8 +7,8 @@ from . import IFieldEncryptor
 class StringListEncryptor(IFieldEncryptor):
     @staticmethod
     def encrypt(value: List[str]):
-        return [get_datastore_encryptor().encrypt(string) for string in value]
+        return [get_datastore_encryptor().encrypt(string.encode()) for string in value]
 
     @staticmethod
-    def decrypt(value: List[str]):
-        return [get_datastore_encryptor().decrypt(string) for string in value]
+    def decrypt(value: List[bytes]):
+        return [get_datastore_encryptor().decrypt(bytes_).decode() for bytes_ in value]
diff --git a/monkey/monkey_island/cc/server_utils/encryption/i_encryptor.py b/monkey/monkey_island/cc/server_utils/encryption/i_encryptor.py
index d46e51c1a..8bc701bf9 100644
--- a/monkey/monkey_island/cc/server_utils/encryption/i_encryptor.py
+++ b/monkey/monkey_island/cc/server_utils/encryption/i_encryptor.py
@@ -1,10 +1,9 @@
 from abc import ABC, abstractmethod
-from typing import Any
 
 
 class IEncryptor(ABC):
     @abstractmethod
-    def encrypt(self, plaintext: Any) -> Any:
+    def encrypt(self, plaintext: bytes) -> bytes:
         """
         Encrypts data and returns the ciphertext.
 
@@ -13,7 +12,7 @@ class IEncryptor(ABC):
         """
 
     @abstractmethod
-    def decrypt(self, ciphertext: Any):
+    def decrypt(self, ciphertext: bytes) -> bytes:
         """
         Decrypts data and returns the plaintext.
 
diff --git a/monkey/monkey_island/cc/server_utils/encryption/key_based_encryptor.py b/monkey/monkey_island/cc/server_utils/encryption/key_based_encryptor.py
index 630094989..67e59f94d 100644
--- a/monkey/monkey_island/cc/server_utils/encryption/key_based_encryptor.py
+++ b/monkey/monkey_island/cc/server_utils/encryption/key_based_encryptor.py
@@ -31,15 +31,15 @@ class KeyBasedEncryptor(IEncryptor):
     #       something up. The main drawback to fernet is that it uses AES-128, which is not
     #       quantum-safe. At the present time, human error is probably a greater risk than quantum
     #       computers.
-    def encrypt(self, plaintext: str) -> str:
+    def encrypt(self, plaintext: bytes) -> bytes:
         cipher_iv = Random.new().read(AES.block_size)
         cipher = AES.new(self._key, AES.MODE_CBC, cipher_iv)
-        padded_plaintext = Padding.pad(plaintext.encode(), self._BLOCK_SIZE)
-        return base64.b64encode(cipher_iv + cipher.encrypt(padded_plaintext)).decode()
+        padded_plaintext = Padding.pad(plaintext, self._BLOCK_SIZE)
+        return base64.b64encode(cipher_iv + cipher.encrypt(padded_plaintext))
 
-    def decrypt(self, ciphertext: str):
+    def decrypt(self, ciphertext: bytes) -> bytes:
         enc_message = base64.b64decode(ciphertext)
         cipher_iv = enc_message[0 : AES.block_size]
         cipher = AES.new(self._key, AES.MODE_CBC, cipher_iv)
         padded_plaintext = cipher.decrypt(enc_message[AES.block_size :])
-        return Padding.unpad(padded_plaintext, self._BLOCK_SIZE).decode()
+        return Padding.unpad(padded_plaintext, self._BLOCK_SIZE)
diff --git a/monkey/tests/unit_tests/monkey_island/cc/server_utils/encryption/test_data_store_encryptor.py b/monkey/tests/unit_tests/monkey_island/cc/server_utils/encryption/test_data_store_encryptor.py
index da4a9ec09..1887185d4 100644
--- a/monkey/tests/unit_tests/monkey_island/cc/server_utils/encryption/test_data_store_encryptor.py
+++ b/monkey/tests/unit_tests/monkey_island/cc/server_utils/encryption/test_data_store_encryptor.py
@@ -11,7 +11,7 @@ from monkey_island.cc.server_utils.encryption import (
 # Mark all tests in this module as slow
 pytestmark = pytest.mark.slow
 
-PLAINTEXT = "Hello, Monkey!"
+PLAINTEXT = b"Hello, Monkey!"
 MOCK_SECRET = "53CR31"
 
 
diff --git a/monkey/tests/unit_tests/monkey_island/cc/server_utils/encryption/test_key_based_encryptor.py b/monkey/tests/unit_tests/monkey_island/cc/server_utils/encryption/test_key_based_encryptor.py
index d41f866a7..d17a5cd1a 100644
--- a/monkey/tests/unit_tests/monkey_island/cc/server_utils/encryption/test_key_based_encryptor.py
+++ b/monkey/tests/unit_tests/monkey_island/cc/server_utils/encryption/test_key_based_encryptor.py
@@ -14,19 +14,19 @@ kb_encryptor = KeyBasedEncryptor(KEY)
 
 
 def test_encrypt_decrypt_string_with_key():
-    encrypted = kb_encryptor.encrypt(PLAINTEXT)
-    decrypted = kb_encryptor.decrypt(encrypted)
+    encrypted = kb_encryptor.encrypt(PLAINTEXT.encode())
+    decrypted = kb_encryptor.decrypt(encrypted).decode()
     assert decrypted == PLAINTEXT
 
 
 @pytest.mark.parametrize("plaintext", [PLAINTEXT_UTF8_1, PLAINTEXT_UTF8_2, PLAINTEXT_UTF8_3])
 def test_encrypt_decrypt_string_utf8_with_key(plaintext):
-    encrypted = kb_encryptor.encrypt(plaintext)
-    decrypted = kb_encryptor.decrypt(encrypted)
+    encrypted = kb_encryptor.encrypt(plaintext.encode())
+    decrypted = kb_encryptor.decrypt(encrypted).decode()
     assert decrypted == plaintext
 
 
 def test_encrypt_decrypt_string_multiple_block_size_with_key():
-    encrypted = kb_encryptor.encrypt(PLAINTEXT_MULTIPLE_BLOCK_SIZE)
-    decrypted = kb_encryptor.decrypt(encrypted)
+    encrypted = kb_encryptor.encrypt(PLAINTEXT_MULTIPLE_BLOCK_SIZE.encode())
+    decrypted = kb_encryptor.decrypt(encrypted).decode()
     assert decrypted == PLAINTEXT_MULTIPLE_BLOCK_SIZE