diff --git a/kdc/fast.c b/kdc/fast.c
index 85fab3310..efdee7107 100644
--- a/kdc/fast.c
+++ b/kdc/fast.c
@@ -632,7 +632,7 @@ fast_unwrap_request(astgs_request_t r,
     if (r->explicit_armor_present) {
 	ret = _krb5_fast_explicit_armor_key(r->context,
 					    &armorkey,
-					    tgs_ac->remote_subkey,
+					    ac->remote_subkey,
 					    &explicit_armorkey,
 					    &r->armor_crypto);
 	if (ret)