diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3f0d18d..2e4b78e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -42,7 +42,7 @@ include_directories(${LIBLZMA_INCLUDE_DIRS})
 find_package(ZLIB)
 include_directories(${ZLIB_INCLUDE_DIRS})
 
-set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 
diff --git a/cmake/external/protobuf.cmake b/cmake/external/protobuf.cmake
index 045db89..b000ab4 100644
--- a/cmake/external/protobuf.cmake
+++ b/cmake/external/protobuf.cmake
@@ -165,6 +165,7 @@ ExternalProject_Add(${PROTOBUF_TARGET}
         -DCMAKE_CXX_COMPILER_LAUNCHER:FILEPATH=${CMAKE_CXX_COMPILER_LAUNCHER}
         -DCMAKE_C_FLAGS=${PROTOBUF_CFLAGS}
         -DCMAKE_CXX_FLAGS=${PROTOBUF_CXXFLAGS}
+        -DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}
         -Dprotobuf_BUILD_TESTS=OFF
     BUILD_BYPRODUCTS ${PROTOBUF_BUILD_BYPRODUCTS}
 )