Dear all, We use unbound since more than a year already with great satisfaction and no issue for resolving 4 Mbps DNS traffic in average with DNSSEC enabled. We used to have unbound 1.4.14. At the end of August suddenly unbound stopped to work. The process killed itself with the following message in the logs: /var/log/messages:Aug 28 19:35:22 hostname unbound: [7896:1] fatal error: services/outside_network.c:1504: serviced_callbacks: pointer whitelist fptr_whitelist_serviced_query(p->cb) failed The machine was under no unusual CPU/Memory/Network load. We thought, bad luck, started the process and everything was fine for one week, when suddenly again the same thing. Fatal error. /var/log/messages:Sep 6 14:20:20 hostname unbound: [1503:0] fatal error: services/outside_network.c:1504: serviced_callbacks: pointer whitelist fptr_whitelist_serviced_query(p->cb) failed Then we thought about our version being too old and we upgraded to the latest release unbound 1.4.18. Now we are running unbound 1.4.18 since two weeks and today again: /var/log/messages:Sep 28 13:59:53 hostname unbound: [1591:1] fatal error: services/outside_network.c:1510: serviced_callbacks: pointer whitelist fptr_whitelist_serviced_query(p->cb) failed Sounds like a software bug? kind regards Leo Bush By the way, even if I do not think it is related to this case, I would like to report on the following behavior, that we note: Several times a day we notice short peaks (<10 minutes) in outgoing traffic (times 7). Even if the traffic is so much higher, we do not notice a performance issue on the server. CPU and Ram are still fine. DNS response times are fine too. A traffic analysis suggested a DNS amplification attack where the question is for ANY isc.org. This attack never was happening when unbound crashed.