Application Layer Protocol: DNS

Adversaries may communicate using the Domain Name System (DNS) application layer protocol to avoid detection/network filtering by blending in with existing traffic. Commands to the remote system, and often the results of those commands, will be embedded within the protocol traffic between the client and server.

The DNS protocol serves an administrative function in computer networking and thus may be very common in environments. DNS traffic may also be allowed even before network authentication is completed. DNS packets contain many fields and headers in which data can be concealed. Often known as DNS tunneling, adversaries may abuse DNS to communicate with systems under their control within a victim network while also mimicking normal, expected traffic.[1][2]

ID: T1071.004
Sub-technique of:  T1071
Platforms: Linux, Windows, macOS
Contributors: Jan Petrov, Citi
Version: 1.0
Created: 15 March 2020
Last Modified: 21 October 2020
Provided by LAYER 8

Procedure Examples

ID Name Description
S0504 Anchor

Variants of Anchor can use DNS tunneling to communicate with C2.[3][4]

G0026 APT18

APT18 uses DNS for C2 communications.[5]

G0087 APT39

APT39 has used remote access tools that leverage DNS in communications with C2.[6]

G0096 APT41

APT41 used DNS for C2 communications.[7][8]


BONDUPDATER can use DNS and TXT records within its DNS tunneling protocol for command and control.[9]

G0114 Chimera

Chimera has used Cobalt Strike to encapsulate C2 in DNS traffic.[10]

G0080 Cobalt Group

Cobalt Group has used DNS tunneling for C2.[11][12][13]

S0154 Cobalt Strike

Cobalt Strike can use a custom command and control protocol that can be encapsulated in DNS. All protocols use their standard assigned ports.[14][15][16]

S0338 Cobian RAT

Cobian RAT uses DNS for C2.[17]

S0354 Denis

Denis has used DNS tunneling for C2 communications.[18][19][20]

S0377 Ebury

Ebury has used DNS requests over UDP port 53 for C2.[21]

G0046 FIN7

FIN7 has performed C2 using DNS via A, OPT, and TXT records.[22]

S0477 Goopy

Goopy has the ability to communicate with its C2 over DNS.[20]

S0170 Helminth

Helminth can use DNS for C2.[23]

S0070 HTTPBrowser

HTTPBrowser has used DNS for command and control.[24][25]

S0260 InvisiMole

InvisiMole has used a custom implementation of DNS tunneling to embed C2 communications in DNS requests and replies.[26]

G0004 Ke3chang

Ke3chang malware RoyalDNS has used DNS for C2.[27]

S0167 Matryoshka

Matryoshka uses DNS for C2.[28][29]

S0228 NanHaiShu

NanHaiShu uses DNS for the C2 communications.[30]

G0049 OilRig

OilRig has used DNS for C2 including the publicly available tunneling service.[31][32][33][34]

S0124 Pisloader

Pisloader uses DNS as its C2 protocol.[35]

S0013 PlugX

PlugX can be configured to use DNS for command and control.[24]


POWERSOURCE uses DNS TXT records for C2.[36][37]


POWRUNER can use DNS for C2 communications.[38][32]


QUADAGENT uses DNS for C2 communications.[39]

S0495 RDAT

RDAT has used DNS to communicate with the C2.[40]

S0125 Remsec

Remsec is capable of using DNS for C2.[41][42][43]

S0596 ShadowPad

ShadowPad has used DNS tunneling for C2 communications.[44]

S0633 Sliver

Sliver can support C2 communications over DNS.[45][46][47]

S0615 SombRAT

SombRAT can communicate over DNS with the C2 server.[48][49]


SOUNDBITE communicates via DNS for C2.[50]


SUNBURST used DNS for C2 traffic designed to mimic normal SolarWinds API communications.[51]


TEXTMATE uses DNS TXT records for C2.[36]

G0081 Tropic Trooper

Tropic Trooper's backdoor has communicated to the C2 over the DNS protocol.[52]

S0514 WellMess

WellMess has the ability to use DNS tunneling for C2 communications.[53][54]


ID Mitigation Description
M1037 Filter Network Traffic

Consider filtering DNS requests to unknown, untrusted, or known bad domains and resources. Resolving DNS requests with on-premise/proxy servers may also disrupt adversary attempts to conceal data within DNS packets.

M1031 Network Intrusion Prevention

Network intrusion detection and prevention systems that use network signatures to identify traffic for specific adversary malware can be used to mitigate activity at the network level.


ID Data Source Data Component
DS0029 Network Traffic Network Traffic Content
Network Traffic Flow

Analyze network data for uncommon data flows (e.g., a client sending significantly more data than it receives from a server). Processes utilizing the network that do not normally have network communication or have never been seen before are suspicious. Analyze packet contents to detect application layer protocols that do not follow the expected protocol standards regarding syntax, structure, or any other variable adversaries could leverage to conceal data.[55]

Monitor for DNS traffic to/from known-bad or suspicious domains.


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  8. Miller, S., et al. (2017, March 7). FIN7 Spear Phishing Campaign Targets Personnel Involved in SEC Filings. Retrieved March 8, 2017.
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