diff --git a/subsys/bluetooth/controller/ll_sw/ull_scan_aux.c b/subsys/bluetooth/controller/ll_sw/ull_scan_aux.c
index d46cfd1dba8930..9f0f6b825b8b67 100644
--- a/subsys/bluetooth/controller/ll_sw/ull_scan_aux.c
+++ b/subsys/bluetooth/controller/ll_sw/ull_scan_aux.c
@@ -411,7 +411,7 @@ void ull_scan_aux_setup(memq_link_t *link, struct node_rx_hdr *rx)
 		 * Setup synchronization if address and SID match in the
 		 * Periodic Advertiser List or with the explicitly supplied.
 		 */
-		if (IS_ENABLED(CONFIG_BT_CTLR_SYNC_PERIODIC) && sync && adi &&
+		if (IS_ENABLED(CONFIG_BT_CTLR_SYNC_PERIODIC) && aux && sync && adi &&
 		    ull_sync_setup_sid_match(scan, PDU_ADV_ADI_SID_GET(adi))) {
 			ull_sync_setup(scan, aux, rx, si);
 		}