diff --git a/source/CMakeLists.txt b/source/CMakeLists.txt
index 459ed5a..41904cd 100644
--- a/source/CMakeLists.txt
+++ b/source/CMakeLists.txt
@@ -75,6 +75,12 @@ if(FORTIFY_FOUND EQUAL -1)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wp,-D_FORTIFY_SOURCE=2")
 endif()
         
+string(FIND "${CMAKE_CXX_FLAGS}" "-D_FORTIFY_SOURCE" FORTIFY_FOUND)
+
+if(FORTIFY_FOUND EQUAL -1)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wp,-D_FORTIFY_SOURCE=2")
+endif()
+
 set(SOURCE_FILES
         ubl-settings-kernel.c
         ubl-settings-kernel.h