diff --git a/src/lib/protocols/stun.c b/src/lib/protocols/stun.c
index 138308082c4..f7c1ab51215 100644
--- a/src/lib/protocols/stun.c
+++ b/src/lib/protocols/stun.c
@@ -675,6 +675,7 @@ static int keep_extra_dissection(struct ndpi_detection_module_struct *ndpi_struc
 
   if(packet->udp
      && (ntohs(packet->udp->source) == 3478)
+     && (packet->payload_packet_len > 0)
      && (packet->payload[0] != 0x0) && (packet->payload[0] != 0x1)) {
     if(flow->stun.num_non_stun_pkt < 2) {
       flow->stun.non_stun_pkt_len[flow->stun.num_non_stun_pkt++] = packet->payload_packet_len;