Skip to content

T1095 Non-Application Layer Protocol

Adversaries may use a non-application layer protocol for communication between host and C2 server or among infected hosts within a network. The list of possible protocols is extensive.1 Specific examples include use of network layer protocols, such as the Internet Control Message Protocol (ICMP), transport layer protocols, such as the User Datagram Protocol (UDP), session layer protocols, such as Socket Secure (SOCKS), as well as redirected/tunneled protocols, such as Serial over LAN (SOL).

ICMP communication between hosts is one example.2 Because ICMP is part of the Internet Protocol Suite, it is required to be implemented by all IP-compatible hosts.3 However, it is not as commonly monitored as other Internet Protocols such as TCP or UDP and may be used by adversaries to hide communications.

Item Value
ID T1095
Tactics TA0011
Platforms Linux, Network, Windows, macOS
Version 2.1
Created 31 May 2017
Last Modified 17 February 2022

Procedure Examples

ID Name Description
S0504 Anchor Anchor has used ICMP in C2 communications.15
G0016 APT29 APT29 has used TCP for C2 communications.59
G0022 APT3 An APT3 downloader establishes SOCKS5 connections for its initial C2.64
S0456 Aria-body Aria-body has used TCP in C2 communications.30
G0135 BackdoorDiplomacy BackdoorDiplomacy has used EarthWorm for network tunneling with a SOCKS5 server and port transfer functionalities.62
S0234 Bandook Bandook has a command built in to use a raw TCP socket.26
S0268 Bisonal Bisonal has used raw sockets for network communication.12
S0043 BUBBLEWRAP BUBBLEWRAP can communicate using SOCKS.40
S0335 Carbon Carbon uses TCP and UDP for C2.13
S0660 Clambling Clambling has the ability to use TCP and UDP for communication.36
S0154 Cobalt Strike Cobalt Strike can be configured to use TCP, ICMP, and UDP for C2 communications.5152
S0115 Crimson Crimson uses a custom TCP protocol for C2.3233
S0498 Cryptoistic Cryptoistic can use TCP in communications with C2.44
S0021 Derusbi Derusbi binds to a raw socket on a random source port between 31800 and 31900 for C2.46
S0502 Drovorub Drovorub can use TCP to communicate between its agent and client modules.8
S0076 FakeM Some variants of FakeM use SSL to communicate with C2 servers.47
G0037 FIN6 FIN6 has used Metasploit Bind and Reverse TCP stagers.63
S0666 Gelsemium Gelsemium has the ability to use TCP and UDP in C2 communications.54
S0032 gh0st RAT gh0st RAT has used an encrypted protocol within TCP segments to communicate with the C2.39
G0125 HAFNIUM HAFNIUM has used TCP for C2.58
S0394 HiddenWasp HiddenWasp communicates with a simple network protocol over TCP.19
S0260 InvisiMole InvisiMole has used TCP to download additional modules.22
S0582 LookBack LookBack uses a custom binary protocol over sockets for C2 communications.49
S0455 Metamorfo Metamorfo has used raw TCP for C2.34
S0084 Mis-Type Mis-Type network traffic can communicate over a raw socket.7
S0083 Misdat Misdat network traffic communicates over a raw socket.7
S0149 MoonWind MoonWind completes network communication via raw sockets.53
S0699 Mythic Mythic supports WebSocket and TCP-based C2 profiles.6
S0630 Nebulae Nebulae can use TCP in C2 communications.25
S0034 NETEAGLE If NETEAGLE does not detect a proxy configured on the infected machine, it will send beacons via UDP/6000. Also, after retrieving a C2 IP address and Port Number, NETEAGLE will initiate a TCP connection to this socket. The ensuing connection is a plaintext C2 channel in which commands are specified by DWORDs.29
S0198 NETWIRE NETWIRE can use TCP in C2 communications.5657
G0116 Operation Wocao Operation Wocao has used a custom protocol for command and control.60
S0556 Pay2Key Pay2Key has sent its public key to the C2 server over TCP.27
S0587 Penquin The Penquin C2 mechanism is based on TCP and UDP packets.910
S0158 PHOREAL PHOREAL communicates via ICMP for C2.11
S0501 PipeMon The PipeMon communication module can use a custom protocol based on TLS over TCP.55
G0068 PLATINUM PLATINUM has used the Intel® Active Management Technology (AMT) Serial-over-LAN (SOL) channel for command and control.61
S0013 PlugX PlugX can be configured to use raw TCP or UDP for command and control.18
S0650 QakBot QakBot has the ability use TCP to send or receive C2 packets.41
S0629 RainyDay RainyDay can use TCP in C2 communications.25
S0055 RARSTONE RARSTONE uses SSL to encrypt its communication with its C2 server.21
S0662 RCSession RCSession has the ability to use TCP and UDP in C2 communications.3637
S0172 Reaver Some Reaver variants use raw TCP for C2.35
S0019 Regin The Regin malware platform can use ICMP to communicate between infected computers.14
S0125 Remsec Remsec is capable of using ICMP, TCP, and UDP for C2.2324
S0461 SDBbot SDBbot has the ability to communicate with C2 with TCP over port 443.50
S0596 ShadowPad ShadowPad has used UDP for C2 communications.20
S0615 SombRAT SombRAT has the ability to use TCP sockets to send data and ICMP to ping the C2 server.4243
S0011 Taidoor Taidoor can use TCP for C2 communications.38
S0436 TSCookie TSCookie can use ICMP to receive information on the destination server.17
S0221 Umbreon Umbreon provides access to the system via SSH or any other protocol that uses PAM to authenticate.45
S0670 WarzoneRAT WarzoneRAT can communicate with its C2 server via TCP over port 5200.28
S0515 WellMail WellMail can use TCP for C2 communications.48
S0155 WINDSHIELD WINDSHIELD C2 traffic can communicate via TCP raw sockets.11
S0430 Winnti for Linux Winnti for Linux has used ICMP, custom TCP, and UDP in outbound communications.31
S0141 Winnti for Windows Winnti for Windows can communicate using custom TCP.16


ID Mitigation Description
M1037 Filter Network Traffic Filter network traffic to prevent use of protocols across the network boundary that are unnecessary.
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.
M1030 Network Segmentation Properly configure firewalls and proxies to limit outgoing traffic to only necessary ports and through proper network gateway systems. Also ensure hosts are only provisioned to communicate over authorized interfaces.


ID Data Source Data Component
DS0029 Network Traffic Network Traffic Content


  1. Wikipedia. (n.d.). List of network protocols (OSI model). Retrieved December 4, 2014. 

  2. Graham Holmes. (2015, October 8). Evolution of attacks on Cisco IOS devices. Retrieved October 19, 2020. 

  3. Microsoft. (n.d.). Internet Control Message Protocol (ICMP) Basics. Retrieved December 1, 2014. 

  4. Omar Santos. (2020, October 19). Attackers Continue to Target Legacy Devices. Retrieved October 20, 2020. 

  5. Gardiner, J., Cova, M., Nagaraja, S. (2014, February). Command & Control Understanding, Denying and Detecting. Retrieved April 20, 2016. 

  6. Thomas, C. (n.d.). Mythc Documentation. Retrieved March 25, 2022. 

  7. Gross, J. (2016, February 23). Operation Dust Storm. Retrieved December 22, 2021. 

  8. NSA/FBI. (2020, August). Russian GRU 85th GTsSS Deploys Previously Undisclosed Drovorub Malware. Retrieved August 25, 2020. 

  9. Baumgartner, K. and Raiu, C. (2014, December 8). The ‘Penquin’ Turla. Retrieved March 11, 2021. 

  10. Leonardo. (2020, May 29). MALWARE TECHNICAL INSIGHT TURLA “Penquin_x64”. Retrieved March 11, 2021. 

  11. Carr, N.. (2017, May 14). Cyber Espionage is Alive and Well: APT32 and the Threat to Global Corporations. Retrieved June 18, 2017. 

  12. Mercer, W., et al. (2020, March 5). Bisonal: 10 years of play. Retrieved January 26, 2022. 

  13. ESET. (2017, March 30). Carbon Paper: Peering into Turla’s second stage backdoor. Retrieved November 7, 2018. 

  14. Kaspersky Lab’s Global Research and Analysis Team. (2014, November 24). THE REGIN PLATFORM NATION-STATE OWNAGE OF GSM NETWORKS. Retrieved December 1, 2014. 

  15. Dahan, A. et al. (2019, December 11). DROPPING ANCHOR: FROM A TRICKBOT INFECTION TO THE DISCOVERY OF THE ANCHOR MALWARE. Retrieved September 10, 2020. 

  16. Novetta Threat Research Group. (2015, April 7). Winnti Analysis. Retrieved February 8, 2017. 

  17. Tomonaga, S.. (2019, September 18). Malware Used by BlackTech after Network Intrusion. Retrieved May 6, 2020. 

  18. Dell SecureWorks Counter Threat Unit Threat Intelligence. (2015, August 5). Threat Group-3390 Targets Organizations for Cyberespionage. Retrieved August 18, 2018. 

  19. Sanmillan, I. (2019, May 29). HiddenWasp Malware Stings Targeted Linux Systems. Retrieved June 24, 2019. 

  20. Kaspersky Lab. (2017, August). ShadowPad: popular server management software hit in supply chain attack. Retrieved March 22, 2021. 

  21. Aquino, M. (2013, June 13). RARSTONE Found In Targeted Attacks. Retrieved December 17, 2015. 

  22. Hromcova, Z. and Cherpanov, A. (2020, June). INVISIMOLE: THE HIDDEN PART OF THE STORY. Retrieved July 16, 2020. 

  23. Symantec Security Response. (2016, August 8). Backdoor.Remsec indicators of compromise. Retrieved August 17, 2016. 

  24. Kaspersky Lab’s Global Research & Analysis Team. (2016, August 9). The ProjectSauron APT. Retrieved August 17, 2016. 

  25. Vrabie, V. (2021, April 23). NAIKON – Traces from a Military Cyber-Espionage Operation. Retrieved June 29, 2021. 

  26. Check Point. (2020, November 26). Bandook: Signed & Delivered. Retrieved May 31, 2021. 

  27. Check Point. (2020, November 6). Ransomware Alert: Pay2Key. Retrieved January 4, 2021. 

  28. Harakhavik, Y. (2020, February 3). Warzone: Behind the enemy lines. Retrieved December 17, 2021. 

  29. FireEye Labs. (2015, April). APT30 AND THE MECHANICS OF A LONG-RUNNING CYBER ESPIONAGE OPERATION. Retrieved May 1, 2015. 

  30. CheckPoint. (2020, May 7). Naikon APT: Cyber Espionage Reloaded. Retrieved May 26, 2020. 

  31. Chronicle Blog. (2019, May 15). Winnti: More than just Windows and Gates. Retrieved April 29, 2020. 

  32. Huss, D. (2016, March 1). Operation Transparent Tribe. Retrieved June 8, 2016. 

  33. Dedola, G. (2020, August 20). Transparent Tribe: Evolution analysis, part 1. Retrieved September 2, 2021. 

  34. Sierra, E., Iglesias, G.. (2018, April 24). Metamorfo Campaigns Targeting Brazilian Users. Retrieved July 30, 2020. 

  35. Grunzweig, J. and Miller-Osborn, J. (2017, November 10). New Malware with Ties to SunOrcal Discovered. Retrieved November 16, 2017. 

  36. Lunghi, D. et al. (2020, February). Uncovering DRBControl. Retrieved November 12, 2021. 

  37. Global Threat Center, Intelligence Team. (2020, December). APT27 Turns to Ransomware. Retrieved November 12, 2021. 

  38. CISA, FBI, DOD. (2021, August). MAR-10292089-1.v2 – Chinese Remote Access Trojan: TAIDOOR. Retrieved August 24, 2021. 

  39. Quinn, J. (2019, March 25). The odd case of a Gh0stRAT variant. Retrieved July 15, 2020. 

  40. FireEye Threat Intelligence. (2015, December 1). China-based Cyber Threat Group Uses Dropbox for Malware Communications and Targets Hong Kong Media Outlets. Retrieved December 4, 2015. 

  41. Kuzmenko, A. et al. (2021, September 2). QakBot technical analysis. Retrieved September 27, 2021. 

  42. The BlackBerry Research and Intelligence Team. (2020, November 12). The CostaRicto Campaign: Cyber-Espionage Outsourced. Retrieved May 24, 2021. 

  43. McLellan, T. and Moore, J. et al. (2021, April 29). UNC2447 SOMBRAT and FIVEHANDS Ransomware: A Sophisticated Financial Threat. Retrieved June 2, 2021. 

  44. Stokes, P. (2020, July 27). Four Distinct Families of Lazarus Malware Target Apple’s macOS Platform. Retrieved August 7, 2020. 

  45. Fernando Mercês. (2016, September 5). Pokémon-themed Umbreon Linux Rootkit Hits x86, ARM Systems. Retrieved March 5, 2018. 

  46. Fidelis Cybersecurity. (2016, February 29). The Turbo Campaign, Featuring Derusbi for 64-bit Linux. Retrieved March 2, 2016. 

  47. Falcone, R. and Miller-Osborn, J.. (2016, January 24). Scarlet Mimic: Years-Long Espionage Campaign Targets Minority Activists. Retrieved February 10, 2016. 

  48. CISA. (2020, July 16). MAR-10296782-3.v1 – WELLMAIL. Retrieved September 29, 2020. 

  49. Raggi, M. Schwarz, D.. (2019, August 1). LookBack Malware Targets the United States Utilities Sector with Phishing Attacks Impersonating Engineering Licensing Boards. Retrieved February 25, 2021. 

  50. Schwarz, D. et al. (2019, October 16). TA505 Distributes New SDBbot Remote Access Trojan with Get2 Downloader. Retrieved May 29, 2020. 

  51. Mavis, N. (2020, September 21). The Art and Science of Detecting Cobalt Strike. Retrieved April 6, 2021. 

  52. Strategic Cyber LLC. (2020, November 5). Cobalt Strike: Advanced Threat Tactics for Penetration Testers. Retrieved April 13, 2021. 

  53. Miller-Osborn, J. and Grunzweig, J.. (2017, March 30). Trochilus and New MoonWind RATs Used In Attack Against Thai Organizations. Retrieved March 30, 2017. 

  54. Dupuy, T. and Faou, M. (2021, June). Gelsemium. Retrieved November 30, 2021. 

  55. Tartare, M. et al. (2020, May 21). No “Game over” for the Winnti Group. Retrieved August 24, 2020. 

  56. Lambert, T. (2020, January 29). Intro to Netwire. Retrieved January 7, 2021. 

  57. Duncan, B. (2020, April 3). GuLoader: Malspam Campaign Installing NetWire RAT. Retrieved January 7, 2021. 

  58. MSTIC. (2021, March 2). HAFNIUM targeting Exchange Servers with 0-day exploits. Retrieved March 3, 2021. 

  59. Dunwoody, M., et al. (2018, November 19). Not So Cozy: An Uncomfortable Examination of a Suspected APT29 Phishing Campaign. Retrieved November 27, 2018. 

  60. Dantzig, M. v., Schamper, E. (2019, December 19). Operation Wocao: Shining a light on one of China’s hidden hacking groups. Retrieved October 8, 2020. 

  61. Kaplan, D, et al. (2017, June 7). PLATINUM continues to evolve, find ways to maintain invisibility. Retrieved February 19, 2018. 

  62. Adam Burgher. (2021, June 10). BackdoorDiplomacy: Upgrading from Quarian to Turian. Retrieved September 1, 2021 

  63. Chen, J. (2019, October 10). Magecart Card Skimmers Injected Into Online Shops. Retrieved September 9, 2020. 

  64. Moran, N., et al. (2014, November 21). Operation Double Tap. Retrieved January 14, 2016. 

Back to top