Not all network events are on DeviceNetworkEvents table

Copper Contributor

Anyone know how network event are being collected in MS Defender for Endpoint. Look like DeviceNetworkEvents does not have all network events. We did a testing using nslookup. Do a nslookup to domain 1. Another hour later do a nslookup to domain 2. Then another hour later do a nslookup to domain 3.


DeviceNetworkEvents only have record for the first nslookup. It did not collect the network events for the second and third nslookup.


DeviceProcessEvents did have all these three nslookup process.

 

Thanks

4 Replies
Hi,
Do you find a solution ? Same issue for me...

Regards,

HA
MDE isn't a 100% complete record, MS has to balance bandwidth and storage costs. End result is some events get dropped, particularly if they are similar to previous events or have no security value. 'host made a DNS request' gets logged elsewhere anyway so there is little value in logging every single DNS lookup as a network event. That's just a guess though, as far as I know there is no official documentation on the event selection process. But take a look at Olaf Hartung's excellent series probing into MDE Internals: https://medium.com/falconforce/sysmon-vs-microsoft-defender-for-endpoint-mde-internals-0x01-1e5663b1...
Hello,

First, thanks a lot for your help.
I also find that without Real time protection/RTP enabled, most of the traffic is not logged...

Regards,

HA
OH, that is interesting, we haven't noticed that. It might explain some weird things we saw in the lab though, I will check it out.