diff --git a/ThirdParty/CMakeLists.txt b/ThirdParty/CMakeLists.txt
index 1ce5c22bc89df8127f5d8ff60f47736d11c01cbe..775ffd7a7175fdba7aadb628aba353fde2ede429 100644
--- a/ThirdParty/CMakeLists.txt
+++ b/ThirdParty/CMakeLists.txt
@@ -262,7 +262,7 @@ else ()
     SOURCE_DIR ${CMAKE_CURRENT_BINARY_DIR}/cxroot/source
     INSTALL_DIR ${CMAKE_CURRENT_BINARY_DIR}/cxroot/source
     CONFIGURE_COMMAND ""
-    BUILD_COMMAND make CX_NO_ROOT=1 ${conex_boost} CORSIKA_DATA=${CORSIKA_DATA} all
+    BUILD_COMMAND make CX_NO_ROOT=1 CORSIKA_8=1 ${conex_boost} CORSIKA_DATA=${CORSIKA_DATA} all
     INSTALL_COMMAND ""
     BUILD_IN_SOURCE ON
     EXCLUDE_FROM_ALL TRUE