diff --git a/lib/dns/rdata/in_1/apl_42.c b/lib/dns/rdata/in_1/apl_42.c
index 67c021062b..ee33fa5c57 100644
--- a/lib/dns/rdata/in_1/apl_42.c
+++ b/lib/dns/rdata/in_1/apl_42.c
@@ -327,7 +327,7 @@ dns_rdata_apl_first(dns_rdata_in_apl_t *apl) {
 	/*
 	 * If no APL return ISC_R_NOMORE.
 	 */
-	if (apl->apl == NULL) {
+	if (apl->apl == NULL || apl->apl_len == 0) {
 		return ISC_R_NOMORE;
 	}