diff --git a/protocol/BUILD b/protocol/BUILD
index 00c706a..ca91498 100644
--- a/protocol/BUILD
+++ b/protocol/BUILD
@@ -504,6 +504,24 @@ cc_library(
     ],
 )
 
+cc_test(
+    name = "dfu_check_test",
+    srcs = ["dfu_check_test.cc"],
+    data = [
+        "//protocol/test:test_data",
+    ],
+    deps = [
+        ":host_cmd",
+        ":dfu_check",
+        ":opentitan_version",
+        "//protocol/test:libhoth_device_mock",
+        "//transports:libhoth_device",
+        "@googletest//:gtest",
+        "@googletest//:gtest_main",
+    ],
+)
+
+
 cc_library(
     name = "util",
     srcs = ["util.c"],
diff --git a/protocol/dfu_check_test.cc b/protocol/dfu_check_test.cc
new file mode 100644
index 0000000..084281b
--- /dev/null
+++ b/protocol/dfu_check_test.cc
@@ -0,0 +1,98 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "dfu_check.h"
+
+#include <fcntl.h>
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+#include <sys/mman.h>
+
+#include <cstdint>
+#include <cstring>
+#include <iomanip>
+
+#include "opentitan_version.h"
+#include "test/libhoth_device_mock.h"
+
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::ElementsAreArray;
+using ::testing::Return;
+
+constexpr char kTestData[] = "protocol/test/dummy.bin";
+
+TEST_F(LibHothTest, dfu_check_test) {
+  int fd = open(kTestData, O_RDONLY, 0);
+  ASSERT_NE(fd, -1);
+
+  struct stat statbuf;
+  ASSERT_EQ(fstat(fd, &statbuf), 0);
+
+  uint8_t* image = reinterpret_cast<uint8_t*>(
+      mmap(NULL, statbuf.st_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0));
+  ASSERT_NE(image, nullptr);
+
+  struct opentitan_image_version rom_ext;
+  struct opentitan_image_version app;
+  libhoth_extract_ot_bundle(image, statbuf.st_size, &rom_ext, &app);
+
+  struct opentitan_get_version_resp mock_response = {};
+
+  mock_response.rom_ext.slots[0].major = 0;
+  mock_response.rom_ext.slots[0].minor = 0;
+  mock_response.rom_ext.slots[1].major = 0;
+  mock_response.rom_ext.slots[1].minor = 0;
+
+  mock_response.app.slots[0].major = 0;
+  mock_response.app.slots[0].minor = 0;
+  mock_response.app.slots[1].major = 0;
+  mock_response.app.slots[1].minor = 0;
+
+  EXPECT_EQ(
+      libhoth_dfu_check(&hoth_dev_, image, statbuf.st_size, &mock_response),
+      LIBHOTH_OK);
+}
+
+TEST_F(LibHothTest, dfu_check_fail) {
+  int fd = open(kTestData, O_RDONLY, 0);
+  ASSERT_NE(fd, -1);
+
+  struct stat statbuf;
+  ASSERT_EQ(fstat(fd, &statbuf), 0);
+
+  uint8_t* image = reinterpret_cast<uint8_t*>(
+      mmap(NULL, statbuf.st_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0));
+  ASSERT_NE(image, nullptr);
+
+  struct opentitan_image_version rom_ext;
+  struct opentitan_image_version app;
+  libhoth_extract_ot_bundle(image, statbuf.st_size, &rom_ext, &app);
+
+  struct opentitan_get_version_resp mock_response = {};
+
+  mock_response.rom_ext.slots[0].major = 0;
+  mock_response.rom_ext.slots[0].minor = 115;
+  mock_response.rom_ext.slots[1].major = 0;
+  mock_response.rom_ext.slots[1].minor = 116;
+
+  mock_response.app.slots[0].major = 0;
+  mock_response.app.slots[0].minor = 2025102930;
+  mock_response.app.slots[1].major = 0;
+  mock_response.app.slots[1].minor = 2025102930;
+
+  EXPECT_EQ(
+      libhoth_dfu_check(&hoth_dev_, image, statbuf.st_size, &mock_response),
+      -1);
+}
diff --git a/protocol/test/BUILD b/protocol/test/BUILD
index 5275b20..30e113f 100644
--- a/protocol/test/BUILD
+++ b/protocol/test/BUILD
@@ -17,3 +17,4 @@ filegroup(
     name = "test_data",
     srcs = glob(["*.bin"]),
 )
+
diff --git a/protocol/test/dummy.bin b/protocol/test/dummy.bin
new file mode 100644
index 0000000..dc6d822
Binary files /dev/null and b/protocol/test/dummy.bin differ