diff --git a/external/external_build.cmake b/external/external_build.cmake
index b5930c3..09fbf1e 100644
--- a/external/external_build.cmake
+++ b/external/external_build.cmake
@@ -151,6 +151,7 @@ if (INTERNAL_NETCDF)
   SET(EXTRA_NC_FLAGS CPPFLAGS=${CONFIGURE_CPP_FLAGS} LDFLAGS=${CONFIGURE_LD_FLAGS} LIBS=${CONFIGURE_LIBS_FLAGS})
   ExternalProject_Add(netcdf
     DOWNLOAD_DIR ${VIDE_DOWNLOAD_CACHE}
+    URL_HASH SHA1SUM=a78018c377c843cf7b941c2cdad0190920192179
     DEPENDS ${hdf5_built}
     PREFIX ${BUILD_PREFIX}/netcdf-prefix
     URL ${NETCDF_URL}