the bug has been reported on https://bugs.launchpad.net/ubuntu/+source/empathy/+bug/1064786

Stracktrace on https://launchpadlibrarian.net/119303231/Stacktrace.txt

"#0  0x00007feed9c3b425 in __GI_raise (sig=<optimized out>) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
        resultvar = 0
        pid = <optimized out>
        selftid = 2840
#1  0x00007feed9c3eb8b in __GI_abort () at abort.c:91
        save_stage = 2
        act = {__sigaction_handler = {sa_handler = 0xb00000800, sa_sigaction = 0xb00000800}, sa_mask = {__val = {36721360, 140663832230984, 140663871654352, 140663590041824, 101, 140734715490472, 140663587941569, 4294967295, 125, 125, 38576336, 3100784, 0, 38934064, 38978672, 140663838347264}}, sa_flags = -604313724, sa_restorer = 0x5}
        sigs = {__val = {32, 0 <repeats 15 times>}}
#2  0x00007feeda24ab87 in g_assertion_message (domain=domain@entry=0x7feedb53450b "tp-glib", file=file@entry=0x7feedb571985 "tls-certificate.c", line=line@entry=253, func=func@entry=0x7feedb571f30 "tls_certificate_got_all_cb", message=<optimized out>) at /build/buildd/glib2.0-2.34.0/./glib/gtestutils.c:1877
        lstr = "253\000\377\177\000\000@q\271Z\377\177\000\000\001\000\000\000\000\000\000\000\362\031W\333\356\177\000"
        s = 0x24ca0d0 ""
#3  0x00007feeda24b0a4 in g_assertion_message_expr (domain=domain@entry=0x7feedb53450b "tp-glib", file=file@entry=0x7feedb571985 "tls-certificate.c", line=line@entry=253, func=func@entry=0x7feedb571f30 "tls_certificate_got_all_cb", expr=expr@entry=0x7feedb5719f2 "cert_data != NULL") at /build/buildd/glib2.0-2.34.0/./glib/gtestutils.c:1888
        s = <optimized out>
#4  0x00007feedb5147f6 in tls_certificate_got_all_cb (proxy=proxy@entry=0x23d70d0, properties=<optimized out>, error=error@entry=0x0, user_data=<optimized out>, weak_object=<optimized out>) at tls-certificate.c:253
        cert_data = 0x0
        self = <optimized out>
        state = 0
        i = <optimized out>
        __PRETTY_FUNCTION__ = "tls_certificate_got_all_cb"
#5  0x00007feedb500603 in _tp_cli_dbus_properties_invoke_callback_get_all (weak_object=<optimized out>, user_data=<optimized out>, generic_callback=0x7feedb5145e0 <tls_certificate_got_all_cb>, args=0x2529740, error=0x0, self=0x23d70d0) at _gen/tp-cli-generic-body.h:1210
No locals.
#6  _tp_cli_dbus_properties_invoke_callback_get_all (self=0x23d70d0, error=0x0, args=0x2529740, generic_callback=0x7feedb5145e0 <tls_certificate_got_all_cb>, user_data=<optimized out>, weak_object=<optimized out>) at _gen/tp-cli-generic-body.h:1193
        callback = 0x7feedb5145e0 <tls_certificate_got_all_cb>
#7  0x00007feedb5067d0 in tp_proxy_pending_call_idle_invoke (p=0x250f700) at proxy-methods.c:155
        pc = 0x250f700
        invoke = <optimized out>
        __PRETTY_FUNCTION__ = "tp_proxy_pending_call_idle_invoke"
#8  0x00007feeda228ab5 in g_main_dispatch (context=0x2381970) at /build/buildd/glib2.0-2.34.0/./glib/gmain.c:2715
        dispatch = 0x7feeda225e60 <g_idle_dispatch>
        was_in_call = 0
        user_data = 0x250f700
        callback = 0x7feedb506760 <tp_proxy_pending_call_idle_invoke>
        cb_funcs = 0x7feeda4d69e0
        cb_data = 0x2521630
        current_source_link = {data = 0x252c470, next = 0x0}
        need_destroy = <optimized out>
        source = 0x252c470
        current = 0x23d2d50
        i = <optimized out>
#9  g_main_context_dispatch (context=context@entry=0x2381970) at /build/buildd/glib2.0-2.34.0/./glib/gmain.c:3219
No locals."