diff --git a/misc.c b/misc.c

index b8d1040d..0134d694 100644

--- a/misc.c

+++ b/misc.c

@@ -1,4 +1,4 @@

-/* $OpenBSD: misc.c,v 1.169 2021/08/09 23:47:44 djm Exp $ */

+/* $OpenBSD: misc.c,v 1.170 2021/09/26 14:01:03 djm Exp $ */

 /*

  * Copyright (c) 2000 Markus Friedl.  All rights reserved.

  * Copyright (c) 2005-2020 Damien Miller.  All rights reserved.

@@ -56,6 +56,7 @@

 #ifdef HAVE_PATHS_H

 # include <paths.h>

 #include <pwd.h>

+#include <grp.h>

 #endif

 #ifdef SSH_TUN_OPENBSD

 #include <net/if.h>

@@ -2695,6 +2696,12 @@ subprocess(const char *tag, const char *command,

 		}

 		closefrom(STDERR_FILENO + 1);

+		if (geteuid() == 0 &&

+		    initgroups(pw->pw_name, pw->pw_gid) == -1) {

+			error("%s: initgroups(%s, %u): %s", tag,

+			    pw->pw_name, (u_int)pw->pw_gid, strerror(errno));

+			_exit(1);

+		}

 		if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1) {

 			error("%s: setresgid %u: %s", tag, (u_int)pw->pw_gid,

 			    strerror(errno));