diff --git a/src/tool_main.c b/src/tool_main.c
index dc980e00c0094f68524bee5bf9eac1243e4c7dbc..b815726c0a426ae62f51e8dabbed6fd62294c52a 100644
--- a/src/tool_main.c
+++ b/src/tool_main.c
@@ -210,9 +210,12 @@ static void main_free(struct GlobalConfig *config)
   convert_cleanup();
   metalink_cleanup();
 #ifdef USE_NSS
-  if(PR_Initialized())
+  if(PR_Initialized()) {
+    /* prevent valgrind from reporting still reachable mem from NSRP arenas */
+    PL_ArenaFinish();
     /* prevent valgrind from reporting possibly lost memory (fd cache, ...) */
     PR_Cleanup();
+  }
 #endif
   free_config_fields(config);