I'm unsure what triggered these events, because I'm using the zabbix_sender quite often in scripts to push data to zabbix. I saw the following segfaults this morning.
Oct 4 09:33:33 zabbix kernel: [3347985.861894] zabbix_sender[17889]: segfault at 1 ip 000000000040fde4 sp 00007fff6a9629f0 error 4 in zabbix_sender[400000+16000]
Oct 4 09:33:33 zabbix kernel: [3347985.863169] zabbix_sender[17916]: segfault at 1 ip 000000000040fde4 sp 00007fff2f1f9ba0 error 4 in zabbix_sender[400000+16000]
Oct 4 09:33:33 zabbix kernel: [3347985.863455] zabbix_sender[17907]: segfault at 1 ip 000000000040fde4 sp 00007fff81d3dcd0 error 4 in zabbix_sender[400000+16000]
Oct 4 09:33:33 zabbix kernel: [3347985.864969] zabbix_sender[17898]: segfault at 1 ip 000000000040fde4 sp 00007fff1f6b4810 error 4 in zabbix_sender[400000+16000]
Oct 4 09:33:33 zabbix kernel: [3347985.865167] zabbix_sender[17901]: segfault at 1 ip 000000000040fde4 sp 00007fff529507c0 error 4 in zabbix_sender[400000+16000]
Oct 4 09:33:33 zabbix kernel: [3347985.866316] zabbix_sender[17892]: segfault at 1 ip 000000000040fde4 sp 00007fff88b349c0 error 4 in zabbix_sender[400000+16000]
Oct 4 09:33:33 zabbix kernel: [3347985.868779] zabbix_sender[17919]: segfault at 1 ip 000000000040fde4 sp 00007fff583e6390 error 4 in zabbix_sender[400000+16000]
Oct 4 09:33:33 zabbix kernel: [3347985.868937] zabbix_sender[17895]: segfault at 1 ip 000000000040fde4 sp 00007fffb6f90e20 error 4 in zabbix_sender[400000+16000]
Oct 4 09:33:33 zabbix kernel: [3347985.869815] zabbix_sender[17922]: segfault at 1 ip 000000000040fde4 sp 00007fff7e8632e0 error 4 in zabbix_sender[400000+16000]
Oct 4 09:33:33 zabbix kernel: [3347985.872430] zabbix_sender[17913]: segfault at 1 ip 000000000040fde4 sp 00007fff2f8953b0 error 4 in zabbix_sender[400000+16000]