diff --git a/PAM/ssh/CMakeLists.txt b/PAM/ssh/CMakeLists.txt
index 58c982b..94cee9c 100755
--- a/PAM/ssh/CMakeLists.txt
+++ b/PAM/ssh/CMakeLists.txt
@@ -101,13 +101,15 @@ set(RAPIDJSON_BUILD_TESTS OFF CACHE BOOL "" FORCE)
 set(RAPIDJSON_BUILD_CXX17 ON CACHE BOOL "" FORCE)
 
 cmake_policy(SET CMP0077 NEW)
-cmake_policy(SET CMP0135 NEW)
+
+if(${CMAKE_VERSION} VERSION_GREATER "3.23.0")
+	cmake_policy(SET CMP0135 NEW)
+endif()
 
 FetchContent_Declare(
   libwebsockets
   URL       https://github.com/warmcat/libwebsockets/archive/refs/tags/v4.3.3.zip
   URL_HASH  MD5=96ad80a3283825a9af6a2d9d1acbd132
-  SYSTEM
 )
 
 FetchContent_MakeAvailable(libwebsockets)
@@ -116,7 +118,6 @@ FetchContent_Declare(
   RapidJSON
   URL       https://github.com/Tencent/rapidjson/archive/refs/tags/v1.1.0.zip
   URL_HASH  MD5=ceb1cf16e693a3170c173dc040a9d2bd
-  SYSTEM
 )
 
 if(NOT RapidJSON_POPULATED)