If you are seeing queries for this domain, than you are likely participating in DNS Amplification attacks and your DNS server is probably reachable from the internet and has recursion enabled.
If you are seeing responses for this domain.. unlucky. You are currently beeing DDOS-ed! Good luck.
IPtables:
There are two iptable rules available. If your distribution supports Iptables 'u32' module pick this one, otherwise use the 'string' rule.
U32:
iptables --insert INPUT -p udp --dport 53 -m u32 --u32 "0x28&0xFFDFDFDF=0x07575241 && 0x2c&0xDFDFDFDF=0x44495348 && 0x30&0xFFDFDFDF=0x03434f4d && 0x34&0xFF000000=0x00000000" -j DROP -m comment --comment "DROP DNS Q wradish.com"
More U32 rules can be found here:
https://github.com/smurfmonitor/dns-iptables-rules/blob/master/domain-blacklist.txt
String:
iptables --insert INPUT -p udp --dport 53 -m string --from 40 --to 53 --algo bm --hex-string '|077772616469736803636f6d00|' -j DROP -m comment --comment "DROP DNS Q wradish.com"
More Iptables rules for the STRING module can be found here:
https://github.com/smurfmonitor/dns-iptables-rules/blob/master/domain-blacklist-string.txt
Source:
178.32.56.245
Name server:
;; ANSWER SECTION:
wradish.com. 2036 IN NS ns20.domaincontrol.com.
wradish.com. 2036 IN NS ns19.domaincontrol.com.
Response:
A 2
MX 2
NS 2
SOA 1
TXT 5
Rsize 3798
Whois
Whois Server Version 2.0
Domain names in the .com and .net domains can now be registered
with many different competing registrars. Go to http://www.internic.net
for detailed information.
Domain Name: WRADISH.COM
Registrar: GODADDY.COM, LLC
Whois Server: whois.godaddy.com
Referral URL: http://registrar.godaddy.com
Name Server: NS19.DOMAINCONTROL.COM
Name Server: NS20.DOMAINCONTROL.COM
Status: clientDeleteProhibited
Status: clientRenewProhibited
Status: clientTransferProhibited
Status: clientUpdateProhibited
Updated Date: 21-apr-2014
Creation Date: 21-apr-2014
Expiration Date: 21-apr-2015
>>> Last update of whois database: Wed, 23 Jul 2014 21:19:40 UTC <<<
NOTICE: The expiration date displayed in this record is the date the
registrar's sponsorship of the domain name registration in the registry is
currently set to expire. This date does not necessarily reflect the expiration
date of the domain name registrant's agreement with the sponsoring
registrar. Users may consult the sponsoring registrar's Whois database to
view the registrar's reported date of expiration for this registration.
The Registry database contains ONLY .COM, .NET, .EDU domains and
Registrars.
