diff --git a/package/vtun/Config.in b/package/vtun/Config.in
index fe1f0d0c92..c1f6d384fc 100644
--- a/package/vtun/Config.in
+++ b/package/vtun/Config.in
@@ -3,6 +3,7 @@ config BR2_PACKAGE_VTUN
 	select BR2_PACKAGE_LZO
 	select BR2_PACKAGE_OPENSSL
 	select BR2_PACKAGE_ZLIB
+	depends on BR2_USE_MMU # fork()
 	help
 	  Tool for easily creating Virtual Tunnels over TCP/IP networks
 	  with traffic shaping, compression, and encryption.