diff --git a/tests/protocols/gmp/core/test_states.py b/tests/protocols/gmp/core/test_states.py
new file mode 100644
index 000000000..e0d0de835
--- /dev/null
+++ b/tests/protocols/gmp/core/test_states.py
@@ -0,0 +1,176 @@
+# SPDX-FileCopyrightText: 2024 Greenbone AG
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+import unittest
+from unittest.mock import MagicMock
+
+from gvm.protocols.gmp.core import Response
+from gvm.protocols.gmp.core._connection import (
+    AwaitingResponseState,
+    Context,
+    ErrorState,
+    InitialState,
+    InvalidStateError,
+    ReceivingDataState,
+)
+
+
+class RequestMock:
+    def __init__(self, data: bytes) -> None:
+        self._data = data
+
+    def __bytes__(self) -> bytes:
+        return self._data
+
+    def __str__(self) -> str:
+        return self._data.decode()
+
+
+class InitialStateTestCase(unittest.TestCase):
+    def test_receive_data(self) -> None:
+        context = MagicMock(spec=Context)
+        state = InitialState()
+        state.__set_context__(context)
+
+        with self.assertRaisesRegex(InvalidStateError, "Invalid State"):
+            state.receive_data(b"some data")
+
+    def test_close(self) -> None:
+        context = MagicMock(spec=Context)
+        state = InitialState()
+        state.__set_context__(context)
+
+        state.close()
+
+        context.__set_state__.assert_not_called()
+
+    def test_send(self) -> None:
+        context = MagicMock(spec=Context)
+        state = InitialState()
+        state.__set_context__(context)
+        request = RequestMock(b"some data")
+
+        data = state.send(request)
+        self.assertEqual(data, b"some data")
+
+        self.assertIsInstance(
+            context.__set_state__.call_args[0][0], AwaitingResponseState
+        )
+
+
+class AwaitingResponseStateTestCase(unittest.TestCase):
+
+    def test_receive_data(self) -> None:
+        context = MagicMock(spec=Context)
+        request = RequestMock(b"<start>")
+        state = AwaitingResponseState(request)
+        state.__set_context__(context)
+
+        response = state.receive_data(b"<element>")
+        self.assertIsNone(response)
+
+        self.assertIsInstance(
+            context.__set_state__.call_args[0][0], ReceivingDataState
+        )
+
+    def test_close(self) -> None:
+        context = MagicMock(spec=Context)
+        request = RequestMock(b"<start>")
+        state = AwaitingResponseState(request)
+        state.__set_context__(context)
+
+        state.close()
+
+        self.assertIsInstance(
+            context.__set_state__.call_args[0][0], InitialState
+        )
+
+    def test_send(self) -> None:
+        context = MagicMock(spec=Context)
+        request = RequestMock(b"<start>")
+        state = AwaitingResponseState(request)
+        state.__set_context__(context)
+
+        with self.assertRaisesRegex(InvalidStateError, "Invalid State"):
+            another_request = RequestMock(b"<element>")
+            state.send(another_request)
+
+
+class ErrorStateTestCase(unittest.TestCase):
+
+    def test_receive_data(self) -> None:
+        context = MagicMock(spec=Context)
+        state = ErrorState()
+        state.__set_context__(context)
+
+        with self.assertRaisesRegex(
+            InvalidStateError,
+            "^The connection is in an error state. Please close the connection.$",
+        ):
+            state.receive_data(b"some data")
+
+    def test_close(self) -> None:
+        context = MagicMock(spec=Context)
+        state = ErrorState()
+        state.__set_context__(context)
+
+        state.close()
+
+        self.assertIsInstance(
+            context.__set_state__.call_args[0][0], InitialState
+        )
+
+    def test_send(self) -> None:
+        context = MagicMock(spec=Context)
+        state = ErrorState()
+        state.__set_context__(context)
+
+        with self.assertRaisesRegex(
+            InvalidStateError,
+            "^The connection is in an error state. Please close the connection.$",
+        ):
+            state.receive_data(b"some data")
+
+
+class ReceivingDataStateTestCase(unittest.TestCase):
+
+    def test_receive_data(self) -> None:
+        context = MagicMock(spec=Context)
+        request = RequestMock(b"<start/>")
+        state = ReceivingDataState(request)
+        state.__set_context__(context)
+
+        response = state.receive_data(b"<response>")
+        self.assertIsNone(response)
+
+        response = state.receive_data(b"</response>")
+        self.assertIsNotNone(response)
+        self.assertIsInstance(response, Response)
+        self.assertEqual(response.data, b"<response></response>")  # type: ignore
+
+        self.assertIsInstance(
+            context.__set_state__.call_args[0][0], InitialState
+        )
+
+    def test_close(self) -> None:
+        context = MagicMock(spec=Context)
+        request = RequestMock(b"<start/>")
+        state = ReceivingDataState(request)
+        state.__set_context__(context)
+
+        state.close()
+
+        self.assertIsInstance(
+            context.__set_state__.call_args[0][0], InitialState
+        )
+
+    def test_send(self) -> None:
+        context = MagicMock(spec=Context)
+        request = RequestMock(b"<start/>")
+        state = ReceivingDataState(request)
+        state.__set_context__(context)
+
+        with self.assertRaisesRegex(InvalidStateError, "Invalid State"):
+            another_request = RequestMock(b"<element>")
+            state.send(another_request)
diff --git a/tests/protocols/gmp/core/test_xml_reader.py b/tests/protocols/gmp/core/test_xml_reader.py
new file mode 100644
index 000000000..510121a59
--- /dev/null
+++ b/tests/protocols/gmp/core/test_xml_reader.py
@@ -0,0 +1,16 @@
+# SPDX-FileCopyrightText: 2020-2024 Greenbone AG
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+import unittest
+
+from gvm.protocols.gmp.core._connection import XmlReader
+
+
+class XmlReaderTestCase(unittest.TestCase):
+    def test_is_end_xml_false(self):
+        reader = XmlReader()
+        reader.start_xml()
+
+        false = reader.is_end_xml()
+        self.assertFalse(false)