Zscaler Blog

In our recent post covering CVE-2015-0311, two of the Command and Control (C&C) domains used in the Domain Generation Algorithm (DGA), mapped back to the same Server IP address - 46.105.251.1. They were also using the same nameservers for resolution:

• ns1.regway.com
• ns2.regway.com

We took a closer look at the domains using these nameservers and found a distinct correlation between the C&C servers being used in this and other, possibly unrelated campaigns. In the past month, we've tracked over 70 domains involved in malware C&C or other malicious activity involving Click Fraud & Ransomware campaigns. These domains were registered via "Domain Context" and use "Regway.com" nameservers for resolution.

To recap, we saw the initial binary was executed via the CVE-2015-0311 exploit, which then attempted resolution of multiple domains that were generated through a DGA:

     


Taking a closer look at these domains, we noticed that they share some commonalities, specifically their nameservers and IPs:

 

Taking a look at other domains registered around that time via "Domain Context" by '[email protected]' and also utilizing "regway.com" for resolution, we find the following 39 domains:

aslfnsdifhsfdsa.com
avzxpjvrndi6g.com
bnxjgqotkqaftj.com
cavnplxhlwjzld.com
dtnvleoidsncuz7i.com
ggrdyqtlgdbpkkjf0e.com
gqzrdawmmvaalpevd0.com
grqtnsmqveprdc8f.com
jacafyfugdnvoov.com
jdioermutrealo.com
jxouhxclhzdlwa1d.com
jzkebkiznfttde.com
kdioqw873-kioas.com
koslnotreamouyer.com
krbewsoiitaciki2s.com
mcoihsopejaue.com
mlhxqydhcjqvei.com
nertafopadertam.com
noieutrabchpowewa.com
nwlxjqxstxclgngbw7.com
nyrtazolas.com
piragikolos.com
pndrdbgijushci.com
qhmbdzygdevxk0m.com
qvllupuqjknz5.com
roppsanaukpovtrwl.com
rwermezqpnf4.com
tuchrtwsabl7b.com
uowcvvknkrtipj.com
vsdylqjfrdqaxzyd.com
vucjunrhckgaiyae.com
vxmsrlsanrcilyb7o.com
vxuiweipowe92j.com
xgihfqovzurg8.com
xmoqu38hasdf0opw.com
xqirefjyjkcn7u.com
yoksfffhvizk8z.com
yyfaimjmocdu.com
zmbkfrdpnaec.com

Looking at the same time period for domains registered through "Domain Context", using "Privacy Protect", and using "regway.com" for resolution, we find an additional 32 domains, which also seem to fit the general theme of a DGA:

394iopwekmcopw.com
agdedopribili.com
asop83uyteramxop.com
balamodaevi.com
cawnqrvbmfgfysdb.com
deertraefople.com
gpsnypbnygqidxj.com
gurtgusinoi.com
gypqlkwgkmzapx33.com
iludyamdostaetsya.com
iqjlyjxplidpbbpuh.com
istinuskazat.com
itdlwcwonkhjrxlzuh.com
jddhbxrssjgqlsr.com
jyjhsvgkpeni0g.com
kbazarnomuondnu.com
kosnetsyanetolko.com
muzhikgusei.com
nabarishispeshil.com
neochenvezhlivo.com
predlinnoihvorostinoi.com
prodavatipravdu.com
retravopoytem.com
sokgtxioqzxvuksf1.com
tamgusyam.com
tuzlynlyvrbrdhrpx.com
vpsbxfdyphdykmlct.com
xnanomailing.com
yamuzhikainevenu.com
ytpliogapddu5.com
zhcjrjolbeuiylkyzx.com
zoidpyjhij36.com

The vast majority of these domains were resolving to Bedep's C&C servers. The following is a POST request to a C&C server from a Bedep infected system containing base64 encoded data:


 

However, some of the domains are being used in other seemingly unrelated malicious campaigns. For example the domain 'xmoqu38hasdf0opw.com' was identifed by Kafeine as hosting a Reveton ransom page. 

Other domains being used to monetize Bedep infections via click fraud include:

394iopwekmcopw.com/ads.php
394iopwekmcopw.com/r.php?key=41c7eed67784325bb935f2b6543ff37d
asop83uyteramxop.com/ads.php?sid=1910
asop83uyteramxop.com/r.php?key=c8a0293dce08d582ca645449d849543d
koslnotreamouyer.com/ads.php?sid=1905
koslnotreamouyer.com/r.php?key=666fe962677224b1799919a70c7c2c9e

And the following domains are intermediaries hosting encrypted files:

kosnetsyanetolko.com/slwsbpetw.eqmh
kdioqw873-kioas.com/asdfsfsdf1.php
nertafopadertam.com/2/showthread.php
nyrtazolas.com/1/search.php
piragikolos.com/asdfsfsdf1.php

Unfortunately, there are several different IPs in use on various ASNs:

   

Conclusions

Attackers continue to move away from single IPs and small IP pools, preferring to distribute the infrastructure across multiple netblocks. This ensures their infrastructure is more resilient to blocks and takedown attempts allowing the attackers to continue to profit from compromised devices. Likewise, if a registrar or nameserver with poor reputation is found, specific actors will continue to leverage them until mitigations are put in place.