diff --git a/externals/cmake-modules/Findcryptopp.cmake b/externals/cmake-modules/Findcryptopp.cmake
index 5e621b364..32e461e04 100644
--- a/externals/cmake-modules/Findcryptopp.cmake
+++ b/externals/cmake-modules/Findcryptopp.cmake
@@ -1,4 +1,5 @@
 if(NOT CRYPTOPP_FOUND)
+    find_package(PkgConfig REQUIRED)
     pkg_search_module(CRYPTOPP_TMP crypto++ cryptopp)
 
     find_path(CRYPTOPP_INCLUDE_DIRS NAMES cryptlib.h