diff --git a/src/libmsc/gsm_04_08_cc.c b/src/libmsc/gsm_04_08_cc.c
index a1fea9a..ba6a197 100644
--- a/src/libmsc/gsm_04_08_cc.c
+++ b/src/libmsc/gsm_04_08_cc.c
@@ -1076,8 +1076,16 @@
 static int gsm48_cc_tx_release(struct gsm_trans *trans, void *arg)
 {
 	struct gsm_mncc *rel = arg;
-	struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 CC REL");
-	struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
+	struct msgb *msg;
+	struct gsm48_hdr *gh;
+
+	if (!trans->msc_a) {
+		LOG_TRANS(trans, LOGL_DEBUG, "Cannot send CC REL, there is no MSC-A connection\n");
+		return -EINVAL;
+	}
+
+	msg = gsm48_msgb_alloc_name("GSM 04.08 CC REL");
+	gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
 
 	gh->msg_type = GSM48_MT_CC_RELEASE;
 
diff --git a/src/libmsc/msc_a.c b/src/libmsc/msc_a.c
index 553761f..b3e2e32 100644
--- a/src/libmsc/msc_a.c
+++ b/src/libmsc/msc_a.c
@@ -1562,6 +1562,15 @@
 {
 	struct ran_msg ran_msg;
 
+	if (!msc_a) {
+		struct gsm48_hdr *gh = msgb_l3(dtap) ? : dtap->data;
+		uint8_t pdisc = gsm48_hdr_pdisc(gh);
+		LOGP(DMSC, LOGL_ERROR, "Attempt to send DTAP to NULL MSC-A, dropping message: %s %s\n",
+		     gsm48_pdisc_name(pdisc), gsm48_pdisc_msgtype_name(pdisc, gsm48_hdr_msg_type(gh)));
+		msgb_free(dtap);
+		return -EIO;
+	}
+
 	if (msc_a->c.ran->type == OSMO_RAT_EUTRAN_SGS) {
 		/* The SGs connection to the MME always is at the MSC-A. */
 		return sgs_iface_tx_dtap_ud(msc_a, dtap);