### Description
Kamailio dies complaining about a bad char in some header. I can say that I just updated from the nightly-devel apt repo, this problem never happened in latest v5.1 release.
### Troubleshooting
#### Reproduction
I don't know how to reproduce yet.
#### Debugging Data
<!-- If you got a core dump, use gdb to extract troubleshooting data - full backtrace, local variables and the list of the code at the issue location.
gdb /path/to/kamailio /path/to/corefile bt full info locals list
If you are familiar with gdb, feel free to attach more of what you consider to be relevant. -->
[BT-FULL_core.kamailio.3329.1540415468.txt](https://github.com/kamailio/kamailio/files/2512570/BT-FULL_core.kamailio.332...) [BT-FULL_core.kamailio.3330.1540415471.txt](https://github.com/kamailio/kamailio/files/2512571/BT-FULL_core.kamailio.333...) [BT-FULL_core.kamailio.3331.1540415467.txt](https://github.com/kamailio/kamailio/files/2512572/BT-FULL_core.kamailio.333...) [BT-FULL_core.kamailio.3333.1540415469.txt](https://github.com/kamailio/kamailio/files/2512573/BT-FULL_core.kamailio.333...) [INFO-LOCALS_core.kamailio.3329.1540415468.txt](https://github.com/kamailio/kamailio/files/2512574/INFO-LOCALS_core.kamailio...) [INFO-LOCALS_core.kamailio.3330.1540415471.txt](https://github.com/kamailio/kamailio/files/2512575/INFO-LOCALS_core.kamailio...) [INFO-LOCALS_core.kamailio.3331.1540415467.txt](https://github.com/kamailio/kamailio/files/2512576/INFO-LOCALS_core.kamailio...) [INFO-LOCALS_core.kamailio.3333.1540415469.txt](https://github.com/kamailio/kamailio/files/2512577/INFO-LOCALS_core.kamailio...) [LIST_core.kamailio.3329.1540415468.txt](https://github.com/kamailio/kamailio/files/2512578/LIST_core.kamailio.3329.1...) [LIST_core.kamailio.3330.1540415471.txt](https://github.com/kamailio/kamailio/files/2512579/LIST_core.kamailio.3330.1...) [LIST_core.kamailio.3331.1540415467.txt](https://github.com/kamailio/kamailio/files/2512580/LIST_core.kamailio.3331.1...) [LIST_core.kamailio.3333.1540415469.txt](https://github.com/kamailio/kamailio/files/2512581/LIST_core.kamailio.3333.1...)
#### Log Messages
<!-- Check the syslog file and if there are relevant log messages printed by Kamailio, add them next, or attach to issue, or provide a link to download them (e.g., to a pastebin site). --> The relevant log lines are:
``` Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/parse_addr_spec.c:718]: parse_addr_spec(): unexpected char [<] in status 6: ["910609864" <sip:;:929] . Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/msg_parser.c:164]: get_hdr_field(): bad to header Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/msg_parser.c:337]: parse_headers(): bad header field [To: "910609864" <sip:;:929<>64@138.99.136.3>;tag=as664d068c#015#012Call-ID: 032f010653fed9170365045a4e1002] Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/parse_addr_spec.c:718]: parse_addr_spec(): unexpected char [<] in status 6: ["910609864" <sip:;:929] . Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/msg_parser.c:164]: get_hdr_field(): bad to header Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/msg_parser.c:337]: parse_headers(): bad header field [To: "910609864" <sip:;:929<>64@138.99.136.3>;tag=as664d068c#015#012Call-ID: 032f010653fed9170365045a4e1002] Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/parse_addr_spec.c:718]: parse_addr_spec(): unexpected char [<] in status 6: ["910609864" <sip:;:929] . Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/msg_parser.c:164]: get_hdr_field(): bad to header Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/msg_parser.c:337]: parse_headers(): bad header field [To: "910609864" <sip:;:929<>64@138.99.136.3>;tag=as664d068c#015#012Call-ID: 032f010653fed9170365045a4e1002] Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: pv [pv_core.c:1892]: pv_get_hdr(): error parsing headers Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/parse_addr_spec.c:718]: parse_addr_spec(): unexpected char [<] in status 6: ["910609864" <sip:;:929] . Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/msg_parser.c:164]: get_hdr_field(): bad to header Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: <core> [core/parser/msg_parser.c:337]: parse_headers(): bad header field [To: "910609864" <sip:;:929<>64@138.99.136.3>;tag=as664d068c#015#012Call-ID: 032f010653fed9170365045a4e1002] Oct 24 16:11:11 sbc01 sbc[3330]: ERROR: pv [pv_core.c:704]: pv_get_callid(): cannot parse Call-Id header ```
#### SIP Traffic
<!-- If the issue is exposed by processing specific SIP messages, grab them with ngrep or save in a pcap file, then add them next, or attach to issue, or provide a link to download them (e.g., to a pastebin site). -->
I have enabled a mirror server to capture all traffic, once the problem happens again I will be able to update this issue with SIP traffic.
### Possible Solutions
### Additional Information
* **Kamailio Version** - output of `kamailio -v`
``` root@sbc01:/var/tmp# kamailio -v version: kamailio 5.2.0-pre1 (x86_64/linux) flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144 MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: unknown compiled with gcc 6.3.0 root@sbc01:/var/tmp# ```
* **Operating System**:
<!-- Details about the operating system, the type: Linux (e.g.,: Debian 8.4, Ubuntu 16.04, CentOS 7.1, ...), MacOS, xBSD, Solaris, ...; Kernel details (output of `uname -a`) -->
``` root@sbc01:/var/tmp# uname -a Linux sbc01.vozelia.com.pa 4.9.0-8-amd64 #1 SMP Debian 4.9.110-3+deb9u6 (2018-10-08) x86_64 GNU/Linux root@sbc01:/var/tmp#
root@sbc01:/var/tmp# lsb_release -a No LSB modules are available. Distributor ID: Debian Description: Debian GNU/Linux 9.5 (stretch) Release: 9.5 Codename: stretch root@sbc01:/var/tmp# ```