diff --git a/subsys/bluetooth/host/adv.c b/subsys/bluetooth/host/adv.c
index dc6856ead2d22f..613bf62fa146ac 100644
--- a/subsys/bluetooth/host/adv.c
+++ b/subsys/bluetooth/host/adv.c
@@ -2195,7 +2195,7 @@ void bt_hci_le_adv_set_terminated(struct net_buf *buf)
 	}
 
 	if (IS_ENABLED(CONFIG_BT_CONN) && !evt->status) {
-		struct bt_conn *conn = bt_conn_lookup_handle(conn_handle);
+		struct bt_conn *conn = bt_conn_lookup_handle(conn_handle, BT_CONN_TYPE_LE);
 
 		if (conn) {
 			if (IS_ENABLED(CONFIG_BT_PRIVACY) &&
diff --git a/subsys/bluetooth/host/br.c b/subsys/bluetooth/host/br.c
index 1d4851686cdd32..6a2b16d6aa5c4f 100644
--- a/subsys/bluetooth/host/br.c
+++ b/subsys/bluetooth/host/br.c
@@ -625,7 +625,7 @@ void bt_hci_read_remote_features_complete(struct net_buf *buf)
 
 	LOG_DBG("status 0x%02x handle %u", evt->status, handle);
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_BR);
 	if (!conn) {
 		LOG_ERR("Can't find conn for handle %u", handle);
 		return;
@@ -666,7 +666,7 @@ void bt_hci_read_remote_ext_features_complete(struct net_buf *buf)
 
 	LOG_DBG("status 0x%02x handle %u", evt->status, handle);
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_BR);
 	if (!conn) {
 		LOG_ERR("Can't find conn for handle %u", handle);
 		return;
diff --git a/subsys/bluetooth/host/conn.c b/subsys/bluetooth/host/conn.c
index b6d95b83ebd163..782f4fd87bd4d8 100644
--- a/subsys/bluetooth/host/conn.c
+++ b/subsys/bluetooth/host/conn.c
@@ -1079,8 +1079,10 @@ void bt_conn_set_state(struct bt_conn *conn, bt_conn_state_t state)
 		    conn->role == BT_CONN_ROLE_PERIPHERAL) {
 
 #if defined(CONFIG_BT_GAP_AUTO_UPDATE_CONN_PARAMS)
-			conn->le.conn_param_retry_countdown =
-				CONFIG_BT_CONN_PARAM_RETRY_COUNT;
+			if (conn->type == BT_CONN_TYPE_LE) {
+				conn->le.conn_param_retry_countdown =
+					CONFIG_BT_CONN_PARAM_RETRY_COUNT;
+			}
 #endif /* CONFIG_BT_GAP_AUTO_UPDATE_CONN_PARAMS */
 
 			k_work_schedule(&conn->deferred_work,
@@ -1205,31 +1207,39 @@ void bt_conn_set_state(struct bt_conn *conn, bt_conn_state_t state)
 	}
 }
 
-struct bt_conn *bt_conn_lookup_handle(uint16_t handle)
+struct bt_conn *bt_conn_lookup_handle(uint16_t handle, int type)
 {
 	struct bt_conn *conn;
 
 #if defined(CONFIG_BT_CONN)
 	conn = conn_lookup_handle(acl_conns, ARRAY_SIZE(acl_conns), handle);
 	if (conn) {
-		return conn;
+		goto found;
 	}
 #endif /* CONFIG_BT_CONN */
 
 #if defined(CONFIG_BT_ISO)
 	conn = conn_lookup_handle(iso_conns, ARRAY_SIZE(iso_conns), handle);
 	if (conn) {
-		return conn;
+		goto found;
 	}
 #endif
 
- #if defined(CONFIG_BT_BREDR)
+#if defined(CONFIG_BT_BREDR)
 	conn = conn_lookup_handle(sco_conns, ARRAY_SIZE(sco_conns), handle);
 	if (conn) {
-		return conn;
+		goto found;
 	}
 #endif
 
+found:
+	if (conn) {
+		if (type & conn->type) {
+			return conn;
+		}
+		LOG_WRN("incompatible handle %u", handle);
+		bt_conn_unref(conn);
+	}
 	return NULL;
 }
 
diff --git a/subsys/bluetooth/host/conn_internal.h b/subsys/bluetooth/host/conn_internal.h
index ce89a65dd45fdb..eac811260c32f8 100644
--- a/subsys/bluetooth/host/conn_internal.h
+++ b/subsys/bluetooth/host/conn_internal.h
@@ -308,7 +308,7 @@ void bt_conn_disconnect_all(uint8_t id);
 struct bt_conn *bt_conn_new(struct bt_conn *conns, size_t size);
 
 /* Look up an existing connection */
-struct bt_conn *bt_conn_lookup_handle(uint16_t handle);
+struct bt_conn *bt_conn_lookup_handle(uint16_t handle, int type);
 
 static inline bool bt_conn_is_handle_valid(struct bt_conn *conn)
 {
diff --git a/subsys/bluetooth/host/direction.c b/subsys/bluetooth/host/direction.c
index 76c4b190b24e36..84ca24126c1921 100644
--- a/subsys/bluetooth/host/direction.c
+++ b/subsys/bluetooth/host/direction.c
@@ -680,7 +680,7 @@ int hci_df_prepare_connection_iq_report(struct net_buf *buf,
 
 	evt = net_buf_pull_mem(buf, sizeof(*evt));
 
-	conn = bt_conn_lookup_handle(sys_le16_to_cpu(evt->conn_handle));
+	conn = bt_conn_lookup_handle(sys_le16_to_cpu(evt->conn_handle), BT_CONN_TYPE_LE);
 	if (!conn) {
 		LOG_ERR("Unknown conn handle 0x%04X for iq samples report",
 			sys_le16_to_cpu(evt->conn_handle));
@@ -732,7 +732,7 @@ int hci_df_vs_prepare_connection_iq_report(struct net_buf *buf,
 
 	evt = net_buf_pull_mem(buf, sizeof(*evt));
 
-	conn = bt_conn_lookup_handle(sys_le16_to_cpu(evt->conn_handle));
+	conn = bt_conn_lookup_handle(sys_le16_to_cpu(evt->conn_handle), BT_CONN_TYPE_LE);
 	if (!conn) {
 		LOG_ERR("Unknown conn handle 0x%04X for iq samples report",
 			sys_le16_to_cpu(evt->conn_handle));
@@ -857,7 +857,7 @@ int hci_df_prepare_conn_cte_req_failed(struct net_buf *buf,
 
 	evt = net_buf_pull_mem(buf, sizeof(*evt));
 
-	conn = bt_conn_lookup_handle(sys_le16_to_cpu(evt->conn_handle));
+	conn = bt_conn_lookup_handle(sys_le16_to_cpu(evt->conn_handle), BT_CONN_TYPE_LE);
 	if (!conn) {
 		LOG_ERR("Unknown conn handle 0x%04X for iq samples report",
 			sys_le16_to_cpu(evt->conn_handle));
diff --git a/subsys/bluetooth/host/hci_core.c b/subsys/bluetooth/host/hci_core.c
index 0713fca69c230f..994cfe32e1011a 100644
--- a/subsys/bluetooth/host/hci_core.c
+++ b/subsys/bluetooth/host/hci_core.c
@@ -447,7 +447,7 @@ static void hci_num_completed_packets(struct net_buf *buf)
 
 		LOG_DBG("handle %u count %u", handle, count);
 
-		conn = bt_conn_lookup_handle(handle);
+		conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_ALL);
 		if (!conn) {
 			LOG_ERR("No connection for handle %u", handle);
 			continue;
@@ -520,7 +520,7 @@ static void hci_acl(struct net_buf *buf)
 		return;
 	}
 
-	conn = bt_conn_lookup_handle(acl(buf)->handle);
+	conn = bt_conn_lookup_handle(acl(buf)->handle, BT_CONN_TYPE_ALL);
 	if (!conn) {
 		LOG_ERR("Unable to find conn for handle %u", acl(buf)->handle);
 		net_buf_unref(buf);
@@ -824,7 +824,7 @@ static void hci_disconn_complete_prio(struct net_buf *buf)
 		return;
 	}
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_ALL);
 	if (!conn) {
 		/* Priority disconnect complete event received before normal
 		 * connection complete event.
@@ -849,7 +849,7 @@ static void hci_disconn_complete(struct net_buf *buf)
 		return;
 	}
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_ALL);
 	if (!conn) {
 		LOG_ERR("Unable to look up conn with handle %u", handle);
 		return;
@@ -1617,7 +1617,7 @@ static void le_remote_feat_complete(struct net_buf *buf)
 	uint16_t handle = sys_le16_to_cpu(evt->handle);
 	struct bt_conn *conn;
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_LE);
 	if (!conn) {
 		LOG_ERR("Unable to lookup conn for handle %u", handle);
 		return;
@@ -1645,7 +1645,7 @@ static void le_data_len_change(struct net_buf *buf)
 	uint16_t handle = sys_le16_to_cpu(evt->handle);
 	struct bt_conn *conn;
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_LE);
 	if (!conn) {
 		LOG_ERR("Unable to lookup conn for handle %u", handle);
 		return;
@@ -1678,7 +1678,7 @@ static void le_phy_update_complete(struct net_buf *buf)
 	uint16_t handle = sys_le16_to_cpu(evt->handle);
 	struct bt_conn *conn;
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_LE);
 	if (!conn) {
 		LOG_ERR("Unable to lookup conn for handle %u", handle);
 		return;
@@ -1774,7 +1774,7 @@ static void le_conn_param_req(struct net_buf *buf)
 	param.latency = sys_le16_to_cpu(evt->latency);
 	param.timeout = sys_le16_to_cpu(evt->timeout);
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_LE);
 	if (!conn) {
 		LOG_ERR("Unable to lookup conn for handle %u", handle);
 		le_conn_param_neg_reply(handle, BT_HCI_ERR_UNKNOWN_CONN_ID);
@@ -1800,7 +1800,7 @@ static void le_conn_update_complete(struct net_buf *buf)
 
 	LOG_DBG("status 0x%02x, handle %u", evt->status, handle);
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_LE);
 	if (!conn) {
 		LOG_ERR("Unable to lookup conn for handle %u", handle);
 		return;
@@ -2020,7 +2020,7 @@ static void hci_encrypt_change(struct net_buf *buf)
 
 	LOG_DBG("status 0x%02x handle %u encrypt 0x%02x", evt->status, handle, evt->encrypt);
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_ALL);
 	if (!conn) {
 		LOG_ERR("Unable to look up conn with handle %u", handle);
 		return;
@@ -2095,7 +2095,7 @@ static void hci_encrypt_key_refresh_complete(struct net_buf *buf)
 
 	LOG_DBG("status 0x%02x handle %u", evt->status, handle);
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_ALL);
 	if (!conn) {
 		LOG_ERR("Unable to look up conn with handle %u", handle);
 		return;
@@ -2151,7 +2151,7 @@ static void bt_hci_evt_read_remote_version_complete(struct net_buf *buf)
 
 	evt = net_buf_pull_mem(buf, sizeof(*evt));
 	handle = sys_le16_to_cpu(evt->handle);
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_ALL);
 	if (!conn) {
 		LOG_ERR("No connection for handle %u", handle);
 		return;
@@ -2232,7 +2232,7 @@ static void le_ltk_request(struct net_buf *buf)
 
 	LOG_DBG("handle %u", handle);
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_LE);
 	if (!conn) {
 		LOG_ERR("Unable to lookup conn for handle %u", handle);
 		return;
diff --git a/subsys/bluetooth/host/iso.c b/subsys/bluetooth/host/iso.c
index 6e9976fa81541f..9becf9ff1e9f46 100644
--- a/subsys/bluetooth/host/iso.c
+++ b/subsys/bluetooth/host/iso.c
@@ -124,7 +124,7 @@ void hci_iso(struct net_buf *buf)
 		return;
 	}
 
-	iso = bt_conn_lookup_handle(iso(buf)->handle);
+	iso = bt_conn_lookup_handle(iso(buf)->handle, BT_CONN_TYPE_ISO);
 	if (iso == NULL) {
 		LOG_ERR("Unable to find conn for handle %u", iso(buf)->handle);
 		net_buf_unref(buf);
@@ -982,7 +982,7 @@ void hci_le_cis_established(struct net_buf *buf)
 	LOG_DBG("status 0x%02x handle %u", evt->status, handle);
 
 	/* ISO connection handles are already assigned at this point */
-	iso = bt_conn_lookup_handle(handle);
+	iso = bt_conn_lookup_handle(handle, BT_CONN_TYPE_ISO);
 	if (!iso) {
 		LOG_ERR("No connection found for handle %u", handle);
 		return;
@@ -1229,7 +1229,7 @@ void hci_le_cis_req(struct net_buf *buf)
 	}
 
 	/* Lookup existing connection with same handle */
-	iso = bt_conn_lookup_handle(cis_handle);
+	iso = bt_conn_lookup_handle(cis_handle, BT_CONN_TYPE_ISO);
 	if (iso) {
 		LOG_ERR("Invalid ISO handle %u", cis_handle);
 		hci_le_reject_cis(cis_handle, BT_HCI_ERR_CONN_LIMIT_EXCEEDED);
@@ -1238,7 +1238,7 @@ void hci_le_cis_req(struct net_buf *buf)
 	}
 
 	/* Lookup ACL connection to attach */
-	acl = bt_conn_lookup_handle(acl_handle);
+	acl = bt_conn_lookup_handle(acl_handle, BT_CONN_TYPE_LE);
 	if (!acl) {
 		LOG_ERR("Invalid ACL handle %u", acl_handle);
 		hci_le_reject_cis(cis_handle, BT_HCI_ERR_UNKNOWN_CONN_ID);
diff --git a/subsys/bluetooth/host/scan.c b/subsys/bluetooth/host/scan.c
index 4aa7ab5b3e41dd..168d7f6ead38aa 100644
--- a/subsys/bluetooth/host/scan.c
+++ b/subsys/bluetooth/host/scan.c
@@ -1201,7 +1201,8 @@ static void bt_hci_le_past_received_common(struct net_buf *buf)
 	}
 
 	sync_info.conn = bt_conn_lookup_handle(
-				sys_le16_to_cpu(evt->conn_handle));
+				sys_le16_to_cpu(evt->conn_handle),
+				BT_CONN_TYPE_LE);
 
 	if (!sync_info.conn) {
 		LOG_ERR("Could not lookup connection handle from PAST");
diff --git a/subsys/bluetooth/host/ssp.c b/subsys/bluetooth/host/ssp.c
index 0c8ba58c218206..814a35b32fb5b1 100644
--- a/subsys/bluetooth/host/ssp.c
+++ b/subsys/bluetooth/host/ssp.c
@@ -779,7 +779,7 @@ void bt_hci_auth_complete(struct net_buf *buf)
 
 	LOG_DBG("status 0x%02x, handle %u", evt->status, handle);
 
-	conn = bt_conn_lookup_handle(handle);
+	conn = bt_conn_lookup_handle(handle, BT_CONN_TYPE_BR);
 	if (!conn) {
 		LOG_ERR("Can't find conn for handle %u", handle);
 		return;