Sorry for being late!
Andreas Herz wrote:
How do you run Suricata?
Nothing fancy really, the installation is acting as a router (iptables w/ nat & ip_forward) for a "small" private network.
Suricata installed from epel, running on the local facing interface:
pcap:
- interface: eth1
with SG/GRO/LRO/TSO/GSO disabled:
ethtool -K eth1 sg off gro off lro off tso off gso off
since Suricata logged a warning suggesting this after upgrading from 3.0.1 - it was just
ethtool -K eth1 rx off tx off gro off
pre 3.1.1
I am also running unbound as a reverse DNS proxy for the local network on this box, binding to eth1.
The alerts logged are:
{"timestamp":"2016-08-16T18:58:55.285853+0200","flow_id":4250627771,"in_iface":"eth1","event_type":"alert","src_ip":"x.x.x.x","src_port":53,"dest_ip":"x.x.x.x","dest_port":42924,"proto":"UDP","tx_id":0,"alert":{"action":"allowed","gid":1,"signature_id":2240002,"rev":1,"signature":"SURICATA DNS malformed request data","category":"","severity":3}}
over and over again.
dest_ip is pretty much every active client on the network including Desktops, Smartphones and Tablets ranging from Windows over Linux/Android to OSX/iOS
The src_ip is listed under DNS_SERVERS in
vars:
address-groups:
For the time being i disabled the two noisy messages
suppress gen_id 1, sig_id 2240002
suppress gen_id 1, sig_id 2200037
to stop it from spamming my dashboard.