diff --git a/daemon/call.c b/daemon/call.c
index 2fb2ad8dc..c614be23a 100644
--- a/daemon/call.c
+++ b/daemon/call.c
@@ -867,6 +867,7 @@ static struct endpoint_map *__get_endpoint_map(struct call_media *media, unsigne
 		return NULL;
 
 	__C_DBG("allocating stream_fds for %u ports", num_ports);
+	MEDIA_CLEAR(media, PUBLIC);
 
 	struct socket_intf_list *il;
 	while ((il = t_queue_pop_head(&intf_sockets))) {
diff --git a/daemon/media_socket.c b/daemon/media_socket.c
index 2ebc4641b..1beff5541 100644
--- a/daemon/media_socket.c
+++ b/daemon/media_socket.c
@@ -2427,6 +2427,10 @@ static bool media_packet_address_check(struct packet_handler_ctx *phc)
 				phc->mp.stream->endpoint.port);
 		goto out;
 	}
+	if (!MEDIA_ISSET(phc->mp.media, PUBLIC)) {
+		__C_DBG("media not answered");
+		goto out;
+	}
 
 	// GH #697 - apparent Asterisk bug where it sends stray RTCP to the RTP port.
 	// work around this by detecting this situation and ignoring the packet for
diff --git a/daemon/sdp.c b/daemon/sdp.c
index 157370af5..a20de5b25 100644
--- a/daemon/sdp.c
+++ b/daemon/sdp.c
@@ -3253,6 +3253,8 @@ int sdp_create(str *out, struct call_monologue *monologue, sdp_ng_flags *flags)
 		if (!sdp_out_add_media(s, media, port))
 			goto err;
 
+		MEDIA_SET(media, PUBLIC);
+
 		/* print media level attributes */
 		print_sdp_media_section(s, media, &sdp_address, copy_media, source_media,
 				rtp_ps, rtp_ps_link, flags);
diff --git a/include/call.h b/include/call.h
index f32770a3f..19d0b49d6 100644
--- a/include/call.h
+++ b/include/call.h
@@ -215,6 +215,7 @@ enum {
 #define MEDIA_FLAG_REAL_SENDONLY		(1LL << 35)
 #define MEDIA_FLAG_SELECT_PT			(1LL << 36)
 #define MEDIA_FLAG_RECRYPT			(1LL << 37)
+#define MEDIA_FLAG_PUBLIC			(1LL << 38)
 
 /* struct call_monologue */
 #define ML_FLAG_REC_FORWARDING			(1LL << 16)
diff --git a/t/auto-daemon-tests-heuristic.pl b/t/auto-daemon-tests-heuristic.pl
index 20e3b5156..80cb34147 100755
--- a/t/auto-daemon-tests-heuristic.pl
+++ b/t/auto-daemon-tests-heuristic.pl
@@ -580,5 +580,56 @@ rcv_no($sock_e);
 
 
 
+($sock_a, $sock_b, $sock_c) = new_call(
+	[qw(198.51.100.1 2188)], # caller
+	[qw(198.51.100.3 2190)], # callee - from SDP
+	[qw(198.51.100.3 2210)], # hijack
+);
+
+($port_a) = offer('offer only', { flags => ['strict source'] }, <<SDP);
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=audio 2188 RTP/AVP 0 8
+c=IN IP4 198.51.100.1
+a=sendrecv
+----------------------------------
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=audio PORT RTP/AVP 0 8
+c=IN IP4 203.0.113.1
+a=rtpmap:0 PCMU/8000
+a=rtpmap:8 PCMA/8000
+a=sendrecv
+a=rtcp:PORT
+SDP
+
+# callee send
+snd($sock_b, $port_a,         rtp(0, 2000, 4000, 0x1234, "\x00" x 160));
+($port_b) = rcv($sock_a, -1, rtpm(0, 2000, 4000, 0x1234, "\x00" x 160));
+rcv_no($sock_b);
+rcv_no($sock_c);
+# hijack send
+snd($sock_c, $port_b, rtp(0, 1001, 3160, 0x1234, "\x00" x 160));
+rcv_no($sock_a);
+rcv_no($sock_b);
+rcv_no($sock_c);
+# callee send, forward, hijack ignored
+snd($sock_b, $port_a,  rtp(0, 2001, 4160, 0x1234, "\x00" x 160));
+rcv($sock_a, $port_b, rtpm(0, 2001, 4160, 0x1234, "\x00" x 160));
+rcv_no($sock_b);
+rcv_no($sock_c);
+
+rcv_no($sock_a);
+rcv_no($sock_b);
+rcv_no($sock_c);
+
+
+
+
+
 #done_testing;NGCP::Rtpengine::AutoTest::terminate('f00');exit;
 done_testing();
diff --git a/t/auto-daemon-tests-redis-json.pl b/t/auto-daemon-tests-redis-json.pl
index 954631846..6563cd265 100755
--- a/t/auto-daemon-tests-redis-json.pl
+++ b/t/auto-daemon-tests-redis-json.pl
@@ -148,7 +148,7 @@ $json_exp = {
 		 'format_str' => '0 8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2228236',
+		 'media_flags' => '274880135180',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -404,7 +404,7 @@ $json_exp = {
 		 'format_str' => '8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2293772',
+		 'media_flags' => '274880200716',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -415,7 +415,7 @@ $json_exp = {
 		 'format_str' => '8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65548',
+		 'media_flags' => '274877972492',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -665,7 +665,7 @@ $json_exp = {
 		 'format_str' => '0 8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2228236',
+		 'media_flags' => '274880135180',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -922,7 +922,7 @@ $json_exp = {
 		 'format_str' => '0 8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2293772',
+		 'media_flags' => '274880200716',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -933,7 +933,7 @@ $json_exp = {
 		 'format_str' => '0 8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65548',
+		 'media_flags' => '274877972492',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -1211,7 +1211,7 @@ $json_exp = {
                          'format_str' => '0 8',
                          'index' => '1',
                          'logical_intf' => 'foo',
-                         'media_flags' => '2293772',
+                         'media_flags' => '274880200716',
                          'protocol' => 'RTP/AVP',
                          'ptime' => '0',
                          'tag' => '1',
@@ -1222,7 +1222,7 @@ $json_exp = {
                          'format_str' => '0 8',
                          'index' => '1',
                          'logical_intf' => 'foo',
-                         'media_flags' => '65548',
+                         'media_flags' => '274877972492',
                          'protocol' => 'RTP/AVP',
                          'ptime' => '0',
                          'tag' => '0',
@@ -1233,7 +1233,7 @@ $json_exp = {
                          'format_str' => '0 8',
                          'index' => '1',
                          'logical_intf' => 'foo',
-                         'media_flags' => '2097156',
+                         'media_flags' => '274880004100',
                          'protocol' => 'RTP/AVP',
                          'ptime' => '0',
                          'tag' => '2',
@@ -1244,7 +1244,7 @@ $json_exp = {
                          'format_str' => '0 8',
                          'index' => '2',
                          'logical_intf' => 'foo',
-                         'media_flags' => '2097156',
+                         'media_flags' => '274880004100',
                          'protocol' => 'RTP/AVP',
                          'ptime' => '0',
                          'tag' => '2',
@@ -1566,12 +1566,12 @@ a=rtcp:PORT
 SDP
 
 
-$json_exp->{'media-1'}{media_flags} = '2293772';
-$json_exp->{'media-0'}{media_flags} = '65548';
+$json_exp->{'media-1'}{media_flags} = '274880200716';
+$json_exp->{'media-0'}{media_flags} = '274877972492';
 $json_exp->{'media-2'}{format_str} = '8';
-$json_exp->{'media-2'}{media_flags} = '2162692';
+$json_exp->{'media-2'}{media_flags} = '274880069636';
 $json_exp->{'media-3'}{format_str} = '8';
-$json_exp->{'media-3'}{media_flags} = '2162692';
+$json_exp->{'media-3'}{media_flags} = '274880069636';
 $json_exp->{'payload_types-2'}[0] = '8/PCMA/8000//0/20//';
 $#{$json_exp->{'payload_types-2'}} = 0;
 $json_exp->{'payload_types-3'}[0] = '8/PCMA/8000//0/20//';
@@ -1653,7 +1653,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65544',
+		 'media_flags' => '274877972488',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -1810,7 +1810,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65544',
+		 'media_flags' => '274877972488',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -1821,7 +1821,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2097156',
+		 'media_flags' => '274880004100',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -2047,7 +2047,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65544',
+		 'media_flags' => '274877972488',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -2058,7 +2058,7 @@ $json_exp = {
 		 'format_str' => '0',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2162692',
+		 'media_flags' => '274880069636',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -2298,7 +2298,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65544',
+		 'media_flags' => '274877972488',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -2309,7 +2309,7 @@ $json_exp = {
 		 'format_str' => '0',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2162692',
+		 'media_flags' => '274880069636',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -2320,7 +2320,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2097156',
+		 'media_flags' => '274880004100',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '2',
@@ -2565,7 +2565,7 @@ a=rtcp:PORT
 SDP
 
 $json_exp->{'media-2'}{format_str} = '0';
-$json_exp->{'media-2'}{media_flags} = '2162692';
+$json_exp->{'media-2'}{media_flags} = '274880069636';
 $json_exp->{'stream-1'}{ps_flags}  = '1179649';
 $json_exp->{'stream-4'}{advertised_endpoint} = '198.51.100.14:6046';
 $json_exp->{'stream-4'}{endpoint}  = '198.51.100.14:6046';
diff --git a/t/auto-daemon-tests-redis.pl b/t/auto-daemon-tests-redis.pl
index 13694786b..ce5d86f48 100755
--- a/t/auto-daemon-tests-redis.pl
+++ b/t/auto-daemon-tests-redis.pl
@@ -147,7 +147,7 @@ $json_exp = {
 		 'format_str' => '0 8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2228236',
+		 'media_flags' => '274880135180',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -405,7 +405,7 @@ $json_exp = {
 		 'format_str' => '8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2293772',
+		 'media_flags' => '274880200716',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -416,7 +416,7 @@ $json_exp = {
 		 'format_str' => '8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65548',
+		 'media_flags' => '274877972492',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -666,7 +666,7 @@ $json_exp = {
 		 'format_str' => '8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2293772',
+		 'media_flags' => '274880200716',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -677,7 +677,7 @@ $json_exp = {
 		 'format_str' => '8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65548',
+		 'media_flags' => '274877972492',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -927,7 +927,7 @@ $json_exp = {
 		 'format_str' => '0 8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2228236',
+		 'media_flags' => '274880135180',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -1184,7 +1184,7 @@ $json_exp = {
 		 'format_str' => '0 8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2293772',
+		 'media_flags' => '274880200716',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -1195,7 +1195,7 @@ $json_exp = {
 		 'format_str' => '0 8',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65548',
+		 'media_flags' => '274877972492',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -1473,7 +1473,7 @@ $json_exp = {
                          'format_str' => '0 8',
                          'index' => '1',
                          'logical_intf' => 'foo',
-                         'media_flags' => '2293772',
+                         'media_flags' => '274880200716',
                          'protocol' => 'RTP/AVP',
                          'ptime' => '0',
                          'tag' => '1',
@@ -1484,7 +1484,7 @@ $json_exp = {
                          'format_str' => '0 8',
                          'index' => '1',
                          'logical_intf' => 'foo',
-                         'media_flags' => '65548',
+                         'media_flags' => '274877972492',
                          'protocol' => 'RTP/AVP',
                          'ptime' => '0',
                          'tag' => '0',
@@ -1495,7 +1495,7 @@ $json_exp = {
                          'format_str' => '0 8',
                          'index' => '1',
                          'logical_intf' => 'foo',
-                         'media_flags' => '2097156',
+                         'media_flags' => '274880004100',
                          'protocol' => 'RTP/AVP',
                          'ptime' => '0',
                          'tag' => '2',
@@ -1506,7 +1506,7 @@ $json_exp = {
                          'format_str' => '0 8',
                          'index' => '2',
                          'logical_intf' => 'foo',
-                         'media_flags' => '2097156',
+                         'media_flags' => '274880004100',
                          'protocol' => 'RTP/AVP',
                          'ptime' => '0',
                          'tag' => '2',
@@ -1828,12 +1828,12 @@ a=rtcp:PORT
 SDP
 
 
-$json_exp->{'media-1'}{media_flags} = '2293772';
-$json_exp->{'media-0'}{media_flags} = '65548';
+$json_exp->{'media-1'}{media_flags} = '274880200716';
+$json_exp->{'media-0'}{media_flags} = '274877972492';
 $json_exp->{'media-2'}{format_str} = '8';
-$json_exp->{'media-2'}{media_flags} = '2162692';
+$json_exp->{'media-2'}{media_flags} = '274880069636';
 $json_exp->{'media-3'}{format_str} = '8';
-$json_exp->{'media-3'}{media_flags} = '2162692';
+$json_exp->{'media-3'}{media_flags} = '274880069636';
 $json_exp->{'payload_types-2'}[0] = '8/PCMA/8000//0/20//';
 $#{$json_exp->{'payload_types-2'}} = 0;
 $json_exp->{'payload_types-3'}[0] = '8/PCMA/8000//0/20//';
@@ -1914,7 +1914,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65544',
+		 'media_flags' => '274877972488',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -2071,7 +2071,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65544',
+		 'media_flags' => '274877972488',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -2082,7 +2082,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2097156',
+		 'media_flags' => '274880004100',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -2308,7 +2308,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65544',
+		 'media_flags' => '274877972488',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -2319,7 +2319,7 @@ $json_exp = {
 		 'format_str' => '0',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2162692',
+		 'media_flags' => '274880069636',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -2559,7 +2559,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '65544',
+		 'media_flags' => '274877972488',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '0',
@@ -2570,7 +2570,7 @@ $json_exp = {
 		 'format_str' => '0',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2162692',
+		 'media_flags' => '274880069636',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '1',
@@ -2581,7 +2581,7 @@ $json_exp = {
 		 'format_str' => '0 8 9',
 		 'index' => '1',
 		 'logical_intf' => 'foo',
-		 'media_flags' => '2097156',
+		 'media_flags' => '274880004100',
 		 'protocol' => 'RTP/AVP',
 		 'ptime' => '0',
 		 'tag' => '2',
@@ -2826,7 +2826,7 @@ a=rtcp:PORT
 SDP
 
 $json_exp->{'media-2'}{format_str} = '0';
-$json_exp->{'media-2'}{media_flags} = '2162692';
+$json_exp->{'media-2'}{media_flags} = '274880069636';
 $json_exp->{'stream-1'}{ps_flags}  = '1179649';
 $json_exp->{'stream-4'}{advertised_endpoint} = '198.51.100.14:6046';
 $json_exp->{'stream-4'}{endpoint}  = '198.51.100.14:6046';