--- a/src/getchar.c	2018-10-03 04:24:53.000000000 -0400
+++ b/src/getchar_1.c	2019-06-18 23:02:45.377000000 -0400
@@ -1433,6 +1433,12 @@ openscript(
 	EMSG(_(e_nesting));
 	return;
     }
+
+    // Disallow sourcing a file in the sandbox, the commands would be executed
+    // later, possibly outside of the sandbox.
+    if (check_secure())
+	return;
+
 #ifdef FEAT_EVAL
     if (ignore_script)
 	/* Not reading from script, also don't open one.  Warning message? */