diff --git a/applications/luci-splash/luasrc/controller/splash/splash.lua b/applications/luci-splash/luasrc/controller/splash/splash.lua
index 5731efc8ca..c209647207 100644
--- a/applications/luci-splash/luasrc/controller/splash/splash.lua
+++ b/applications/luci-splash/luasrc/controller/splash/splash.lua
@@ -19,7 +19,10 @@ function action_dispatch()
 end
 
 function action_activate()
-	local mac = luci.sys.net.ip4mac(luci.http.getenv("REMOTE_ADDR"))
+	local ip = luci.http.getenv("REMOTE_ADDR") or "127.0.0.1"
+	local mac = luci.sys.net.ip4mac(
+		ip:match("::") and (ip:gsub("^%[::ffff:(.+)%]", "%1")) or ip
+	)
 	if mac and luci.http.formvalue("accept") then
 		os.execute("luci-splash add "..mac.." >/dev/null 2>&1")
 		luci.http.redirect(luci.model.uci.cursor():get("freifunk", "community", "homepage"))