diff --git a/gocrypt.bash b/gocrypt.bash
index f0cacfa..d33c97c 100755
--- a/gocrypt.bash
+++ b/gocrypt.bash
@@ -67,6 +67,7 @@ gocrypt_init() {
     if $needs_passphrase; then
         echo -n "Enter passphrase: "
         read -s passphrase
+        [[ "$passphrase" =~ [^a-zA-Z0-9\ ] ]] && gocrypt_die "Only alphanumeric characters are allowed for now"
         local passphrase_confirm=""
         echo
         echo -n "Confirm passphrase: "