Once I increased package memory the crash went away.
4(21729) DEBUG: <core> [parser/msg_parser.c:623]: SIP Request: 4(21729) DEBUG: <core> [parser/msg_parser.c:625]: method: <MESSAGE> 4(21729) DEBUG: <core> [parser/msg_parser.c:627]: uri: sip:50.62.72.174:15060;transport=udp 4(21729) DEBUG: <core> [parser/msg_parser.c:629]: version: <SIP/2.0> 0(21722) ALERT: <core> [main.c:788]: child process 21729 exited by a signal 11 0(21722) ALERT: <core> [main.c:791]: core was generated 0(21722) INFO: <core> [main.c:803]: INFO: terminating due to SIGCHLD
(gdb) backtrace #0 qm_detach_free (qm=0x2b7b70759010, size=64) at mem/q_malloc.c:269 #1 qm_malloc (qm=0x2b7b70759010, size=64) at mem/q_malloc.c:386 #2 0x0000000000560fa1 in parse_via ( buffer=0x8c6a3b "SIP/2.0/UDP 50.62.72.174;branch=z9hG4bK3f84.7fd8a5e.0;i=3\r\nVia: SIP/2.0/TCP 75.43.10.221:60659;rport=60660;branch=z9hG4bKPjc9713006b62149648240ed4ea4686b85\r\nMax-Forwards: 16\r\nFrom: <sip:578626051@50.6"..., end=0x8c6e7d "", vbody=0x2b7b7077ae90) at parser/parse_via.c:2540 #3 0x0000000000538e68 in get_hdr_field ( buf=<value optimized out>, end=0x8c6e7d "", hdr=0x2b7b707aa9c0) at parser/msg_parser.c:140 #4 0x0000000000539ac9 in parse_headers (msg=0x2b7b7079b100, flags=2, next=<value optimized out>) at parser/msg_parser.c:351 #5 0x000000000053af8d in parse_msg ( buf=<value optimized out>, len=<value optimized out>, msg=0x2b7b7079b100) at parser/msg_parser.c:650 #6 0x000000000049a2ef in receive_msg ( buf=0x8c6a00 "MESSAGE sip:50.62.72.174:15060;transport=udp SIP/2.0\r\nVia: SIP/2.0/UDP 50.62.72.174;branch=z9hG4bK3f84.7fd8a5e.0;i=3\r\nVia: SIP/2.0/TCP 75.43.10.221:60659;rport=60660;branch=z9hG4bKPjc9713006b621496482"..., len=1149, rcv_info=0x7fff932d32e0) at receive.c:144 #7 0x0000000000528666 in udp_rcv_loop () at udp_server.c:557 #8 0x0000000000464daa in main_loop () at main.c:1638 #9 0x0000000000467adc in main (argc=<value optimized out>, argv=<value optimized out>) at main.c:2566