Exfiltration Over Command and Control Channel

Data exfiltration is performed over the Command and Control channel. Data is encoded into the normal communications channel using the same protocol as command and control communications.

ID: T1041
Tactic: Exfiltration
Platform: Linux, macOS, Windows
Data Sources: User interface, Process monitoring
Requires Network:  Yes
Version: 1.0

Procedure Examples

Name Description
ADVSTORESHELL ADVSTORESHELL exfiltrates data over the same channel used for C2. [6]
APT3 APT3 has a tool that exfiltrates data over the C2 channel. [25]
APT32 APT32's backdoor has exfiltrated data using the already opened channel with its C&C server. [27]
Astaroth Astaroth exfiltrates collected information from its r1.log file to the external C2 server. [14]
BACKSPACE Adversaries can direct BACKSPACE to upload files to the C2 Server. [5]
Bankshot Bankshot exfiltrates data over its C2 channel. [4]
CallMe CallMe exfiltrates data to its C2 server over the same protocol as C2 communications. [8]
Cannon Cannon exfiltrates collected data over email via SMTP/S and POP3/S C2 channels. [11]
Emotet Emotet has been seen exfiltrating system information stored within cookies sent within an HTTP GET request back to its C2 servers. [13]
Empire Empire can send data gathered from a target through the command and control channel. [3]
Gamaredon Group A Gamaredon Group file stealer transfers collected files to a hardcoded C2 server. [9]
HAWKBALL HAWKBALL has sent system information and files over the C2 channel. [17]
HOPLIGHT HOPLIGHT has used its C2 channel to exfiltrate data. [16]
Ke3chang Ke3chang transferred compressed and encrypted RAR files containing exfiltration through the established backdoor command and control channel during operations. [26]
Kimsuky Kimsuky has exfiltrated data over its email C2 channel. [29]
Lazarus Group Lazarus Group malware IndiaIndia saves information gathered about the victim to a file that is uploaded to one of its 10 C2 servers. Another Lazarus Group malware sample also performs exfiltration over the C2 channel. [21] [22] [23]
LightNeuron LightNeuron exfiltrates data over its email C2 channel. [18]
Machete Machete's collected data is exfiltrated over the same channel used for C2. [20]
MobileOrder MobileOrder exfiltrates data to its C2 server over the same protocol as C2 communications. [8]
NETEAGLE NETEAGLE is capable of reading files over the C2 channel. [5]
OopsIE OopsIE can upload files from the victim's machine to its C2 server. [12]
Proxysvc Proxysvc performs data exfiltration over the control server channel using a custom protocol. [10]
Psylo Psylo exfiltrates data to its C2 server over the same protocol as C2 communications. [8]
Pteranodon Pteranodon exfiltrates screenshot files to its C2 server. [9]
Pupy Pupy can send screenshots files, keylogger data, files, and recorded audio back to the C2 server. [2]
Remexi Remexi performs exfiltration over BITSAdmin, which is also used for the C2 channel. [15]
ROKRAT ROKRAT sends collected files back over same C2 channel. [7]
Soft Cell Soft Cell used Web shells and HTRAN for C2 as well as to exfiltrate data. [28]
Stealth Falcon After data is collected by Stealth Falcon malware, it is exfiltrated over the existing C2 channel. [24]
Zebrocy Zebrocy has exfiltrated data to the designated C2 server using HTTP POST requests. [19]

Mitigations

Mitigation Description
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. Signatures are often for unique indicators within protocols and may be based on the specific obfuscation technique used by a particular adversary or tool, and will likely be different across various malware families and versions. Adversaries will likely change tool command and control signatures over time or construct protocols in such a way to avoid detection by common defensive tools. [1]

Detection

Detection for command and control applies. 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 communications that do not follow the expected protocol behavior for the port that is being used. [1]

References

  1. Gardiner, J., Cova, M., Nagaraja, S. (2014, February). Command & Control Understanding, Denying and Detecting. Retrieved April 20, 2016.
  2. Nicolas Verdier. (n.d.). Retrieved January 29, 2018.
  3. Schroeder, W., Warner, J., Nelson, M. (n.d.). Github PowerShellEmpire. Retrieved April 28, 2016.
  4. Sherstobitoff, R. (2018, March 08). Hidden Cobra Targets Turkish Financial Sector With New Bankshot Implant. Retrieved May 18, 2018.
  5. FireEye Labs. (2015, April). APT30 AND THE MECHANICS OF A LONG-RUNNING CYBER ESPIONAGE OPERATION. Retrieved May 1, 2015.
  6. ESET. (2016, October). En Route with Sednit - Part 2: Observing the Comings and Goings. Retrieved November 21, 2016.
  7. Mercer, W., Rascagneres, P. (2017, April 03). Introducing ROKRAT. Retrieved May 21, 2018.
  8. Falcone, R. and Miller-Osborn, J.. (2016, January 24). Scarlet Mimic: Years-Long Espionage Campaign Targets Minority Activists. Retrieved February 10, 2016.
  9. Kasza, A. and Reichel, D.. (2017, February 27). The Gamaredon Group Toolset Evolution. Retrieved March 1, 2017.
  10. Sherstobitoff, R., Malhotra, A. (2018, April 24). Analyzing Operation GhostSecret: Attack Seeks to Steal Data Worldwide. Retrieved May 16, 2018.
  11. Falcone, R., Lee, B. (2018, November 20). Sofacy Continues Global Attacks and Wheels Out New ‘Cannon’ Trojan. Retrieved November 26, 2018.
  12. Lee, B., Falcone, R. (2018, February 23). OopsIE! OilRig Uses ThreeDollars to Deliver New Trojan. Retrieved July 16, 2018.
  13. Trend Micro. (2019, January 16). Exploring Emotet's Activities . Retrieved March 25, 2019.
  14. Salem, E. (2019, February 13). ASTAROTH MALWARE USES LEGITIMATE OS AND ANTIVIRUS PROCESSES TO STEAL PASSWORDS AND PERSONAL DATA. Retrieved April 17, 2019.
  15. Legezo, D. (2019, January 30). Chafer used Remexi malware to spy on Iran-based foreign diplomatic entities. Retrieved April 17, 2019.
  1. US-CERT. (2019, April 10). MAR-10135536-8 – North Korean Trojan: HOPLIGHT. Retrieved April 19, 2019.
  2. Patil, S. and Williams, M.. (2019, June 5). Government Sector in Central Asia Targeted With New HAWKBALL Backdoor Delivered via Microsoft Office Vulnerabilities. Retrieved June 20, 2019.
  3. Faou, M. (2019, May). Turla LightNeuron: One email away from remote code execution. Retrieved June 24, 2019.
  4. Accenture Security. (2018, November 29). SNAKEMACKEREL. Retrieved April 15, 2019.
  5. ESET. (2019, July). MACHETE JUST GOT SHARPER Venezuelan government institutions under attack. Retrieved September 13, 2019.
  6. Novetta Threat Research Group. (2016, February 24). Operation Blockbuster: Unraveling the Long Thread of the Sony Attack. Retrieved February 25, 2016.
  7. Novetta Threat Research Group. (2016, February 24). Operation Blockbuster: Loaders, Installers and Uninstallers Report. Retrieved March 2, 2016.
  8. Sherstobitoff, R. (2018, February 12). Lazarus Resurfaces, Targets Global Banks and Bitcoin Users. Retrieved February 19, 2018.
  9. Marczak, B. and Scott-Railton, J.. (2016, May 29). Keep Calm and (Don’t) Enable Macros: A New Threat Actor Targets UAE Dissidents. Retrieved June 8, 2016.
  10. Chen, X., Scott, M., Caselden, D.. (2014, April 26). New Zero-Day Exploit targeting Internet Explorer Versions 9 through 11 Identified in Targeted Attacks. Retrieved January 14, 2016.
  11. Villeneuve, N., Bennett, J. T., Moran, N., Haq, T., Scott, M., & Geers, K. (2014). OPERATION “KE3CHANG”: Targeted Attacks Against Ministries of Foreign Affairs. Retrieved November 12, 2014.
  12. Dumont, R. (2019, March 20). Fake or Fake: Keeping up with OceanLotus decoys. Retrieved April 1, 2019.
  13. Cybereason Nocturnus. (2019, June 25). Operation Soft Cell: A Worldwide Campaign Against Telecommunications Providers. Retrieved July 18, 2019.
  14. Tarakanov , D.. (2013, September 11). The “Kimsuky” Operation: A North Korean APT?. Retrieved August 13, 2019.