diff -up vim80/src/getchar.c.cve vim80/src/getchar.c
--- vim80/src/getchar.c.cve	2019-06-14 13:46:17.269523985 +0200
+++ vim80/src/getchar.c	2019-06-14 13:46:58.427169288 +0200
@@ -1418,6 +1418,12 @@ 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? */