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T1049 System Network Connections Discovery

Adversaries may attempt to get a listing of network connections to or from the compromised system they are currently accessing or from remote systems by querying for information over the network.

An adversary who gains access to a system that is part of a cloud-based environment may map out Virtual Private Clouds or Virtual Networks in order to determine what systems and services are connected. The actions performed are likely the same types of discovery techniques depending on the operating system, but the resulting information may include details about the networked cloud environment relevant to the adversary’s goals. Cloud providers may have different ways in which their virtual networks operate.123 Similarly, adversaries who gain access to network devices may also perform similar discovery activities to gather information about connected systems and services.

Utilities and commands that acquire this information include netstat, “net use,” and “net session” with Net. In Mac and Linux, netstat and lsof can be used to list current connections. who -a and w can be used to show which users are currently logged in, similar to “net session”. Additionally, built-in features native to network devices and Network Device CLI may be used.4

Item Value
ID T1049
Sub-techniques
Tactics TA0007
Platforms IaaS, Linux, Network, Windows, macOS
Version 2.3
Created 31 May 2017
Last Modified 20 April 2022

Procedure Examples

ID Name Description
G0018 admin@338 admin@338 actors used the following command following exploitation of a machine with LOWBALL malware to display network connections: netstat -ano >> %temp%\download84
G0138 Andariel Andariel has used the netstat -naop tcp command to display TCP connections on a victim’s machine.87
G0006 APT1 APT1 used the net use command to get a listing on network connections.86
G0022 APT3 APT3 has a tool that can enumerate current network connections.357374
G0050 APT32 APT32 used the netstat -anpo tcp command to display TCP connections on the victim’s machine.60
G0082 APT38 APT38 installed a port monitoring tool, MAPMAKER, to print the active TCP connections on the local system.65
G0096 APT41 APT41 has enumerated IP addresses of network resources and used the netstat command as part of network reconnaissance. The group has also used a malware variant, HIGHNOON, to enumerate active RDP sessions.7576
S0456 Aria-body Aria-body has the ability to gather TCP and UDP table status listings.41
S0638 Babuk Babuk can use “WNetOpenEnumW” and “WNetEnumResourceW” to enumerate files in network resources for encryption.40
G0135 BackdoorDiplomacy BackdoorDiplomacy has used NetCat and PortQry to enumerate network connections and display the status of related TCP and UDP ports.71
S0089 BlackEnergy BlackEnergy has gathered information about local network connections using netstat.3132
S0335 Carbon Carbon uses the netstat -r and netstat -an commands.43
S0674 CharmPower CharmPower can use netsh wlan show profiles to list specific Wi-Fi profile details.39
G0114 Chimera Chimera has used netstat -ano
S0154 Cobalt Strike Cobalt Strike can produce a sessions report from compromised hosts.49
S0244 Comnie Comnie executes the netstat -ano command.58
S0575 Conti Conti can enumerate routine network connections from a compromised host.29
S0488 CrackMapExec CrackMapExec can discover active sessions for a targeted system.5
S0625 Cuba Cuba can use the function GetIpNetTable to recover the last connections to the victim’s machine.16
S0567 Dtrack Dtrack can collect network and active connection information.56
S0038 Duqu The discovery modules used with Duqu can collect information on network connections.53
S0554 Egregor Egregor can enumerate all connected drives.45
S0363 Empire Empire can enumerate the current network connections of a host.10
S0091 Epic Epic uses the net use, net session, and netstat commands to gather information on network connections.2223
S0696 Flagpro Flagpro has been used to execute netstat -ano on a compromised host.30
G0093 GALLIUM GALLIUM used netstat -oan to obtain information about the victim network connections.72
S0237 GravityRAT GravityRAT uses the netstat command to find open ports on the victim’s machine.57
S0283 jRAT jRAT can list network connections.15
G0004 Ke3chang Ke3chang performs local network connection discovery using netstat.6667
S0356 KONNI KONNI has used net session on the victim’s machine.54
S0236 Kwampirs Kwampirs collects a list of active and listening connections by using the command netstat -nao as well as a list of available network mappings with net use.13
G0032 Lazarus Group Lazarus Group has used net use to identify and establish a network connection with a remote host.78
S0681 Lizar Lizar has a plugin to retrieve information about all active network sessions on the infected server.18
S0532 Lucifer Lucifer can identify the IP and port numbers for all remote connections from the compromised host.33
S0409 Machete Machete uses the netsh wlan show networks mode=bssid and netsh wlan show interfaces commands to list all nearby WiFi networks and connected interfaces.52
S0449 Maze Maze has used the “WNetOpenEnumW”, “WNetEnumResourceW”, “WNetCloseEnum” and “WNetAddConnection2W” functions to enumerate the network resources on the infected machine.51
G0045 menuPass menuPass has used net use to conduct connectivity checks to machines.81
S0443 MESSAGETAP After loading the keyword and phone data files, MESSAGETAP begins monitoring all network connections to and from the victim server. 24
G0069 MuddyWater MuddyWater has used a PowerShell backdoor to check for Skype connections on the target machine.61
G0129 Mustang Panda Mustang Panda has used netstat -ano to determine network connection information.85
S0102 nbtstat nbtstat can be used to discover current NetBIOS sessions.
S0039 Net Commands such as net use and net session can be used in Net to gather information about network connections from a particular host.9
S0104 netstat netstat can be used to enumerate local network connections, including active TCP connections and other network statistics.7
S0198 NETWIRE NETWIRE can capture session logon details from a compromised host.59
G0049 OilRig OilRig has used netstat -an on a victim to get a listing of network connections.77
S0439 Okrum Okrum was seen using NetSess to discover NetBIOS sessions.50
G0116 Operation Wocao Operation Wocao has collected a list of open connections on the infected system using netstat and checks whether it has an internet connection.63
S0165 OSInfo OSInfo enumerates the current network connections similar to net use .35
S0013 PlugX PlugX has a module for enumerating TCP and UDP network connections and associated processes using the netstat command.36
G0033 Poseidon Group Poseidon Group obtains and saves information about victim network interfaces and addresses.70
S0378 PoshC2 PoshC2 contains an implementation of netstat to enumerate TCP and UDP connections.12
S0184 POWRUNER POWRUNER may collect active network connections by running netstat -an on a victim.21
S0192 Pupy Pupy has a built-in utility command for netstat, can do net session through PowerView, and has an interactive shell which can be used to discover additional information.6
S0650 QakBot QakBot can use netstat to enumerate current network connections.55
S0458 Ramsay Ramsay can use netstat to enumerate network connections.47
S0241 RATANKBA RATANKBA uses netstat -ano to search for specific IP address ranges.14
S0153 RedLeaves RedLeaves can enumerate drives and Remote Desktop sessions.46
S0125 Remsec Remsec can obtain a list of active connections and open ports.17
G0034 Sandworm Team Sandworm Team had gathered user, IP address, and server data related to RDP sessions on a compromised host. It has also accessed network diagram files useful for understanding how a host’s network was configured.6869
S0445 ShimRatReporter ShimRatReporter used the Windows function GetExtendedUdpTable to detect connected UDP endpoints.8
S0063 SHOTPUT SHOTPUT uses netstat to list TCP connection status.20
S0589 Sibot Sibot has retrieved a GUID associated with a present LAN connection on a compromised machine.38
S0633 Sliver Sliver can collect network connection information.11
S0533 SLOTHFULMEDIA SLOTHFULMEDIA can enumerate open ports on a victim machine.37
S0374 SpeakUp SpeakUp uses the arp -a command. 44
S0018 Sykipot Sykipot may use netstat -ano to display active network connections.25
G0139 TeamTNT TeamTNT runs netstat -anp to search for rival malware connections.82 TeamTNT has also used libprocesshider to modify /etc/ld.so.preload.83
G0027 Threat Group-3390 Threat Group-3390 has used net use and netstat to conduct internal discovery of systems. The group has also used quser.exe to identify existing RDP sessions on a victim.64
S0678 Torisma Torisma can use WTSEnumerateSessionsW to monitor remote desktop connections.28
S0094 Trojan.Karagany Trojan.Karagany can use netstat to collect a list of network connections.26
G0081 Tropic Trooper Tropic Trooper has tested if the localhost network is available and other connection capability on an infected system using command scripts.48
G0010 Turla Turla surveys a system upon check-in to discover active local network connections using the netstat -an, net use, net file, and net session commands.2279 Turla RPC backdoors have also enumerated the IPv4 TCP connection table via the GetTcpTable2 API call.80
S0452 USBferry USBferry can use netstat and nbtstat to detect active network connections.48
S0180 Volgmer Volgmer can gather information about TCP connection state.27
S0579 Waterbear Waterbear can use API hooks on GetExtendedTcpTable to retrieve a table containing a list of TCP endpoints available to the application.42
S0689 WhisperGate WhisperGate can enumerate connected remote logical drives.34
S0251 Zebrocy Zebrocy uses netstat -aon to gather network connection information.19

Detection

ID Data Source Data Component
DS0017 Command Command Execution
DS0009 Process OS API Execution

References


  1. Amazon. (n.d.). What Is Amazon VPC?. Retrieved October 6, 2019. 

  2. Annamalai, N., Casey, C., Almeida, M., et. al.. (2019, June 18). What is Azure Virtual Network?. Retrieved October 6, 2019. 

  3. Google. (2019, September 23). Virtual Private Cloud (VPC) network overview. Retrieved October 6, 2019. 

  4. US-CERT. (2018, April 20). Alert (TA18-106A) Russian State-Sponsored Cyber Actors Targeting Network Infrastructure Devices. Retrieved October 19, 2020. 

  5. byt3bl33d3r. (2018, September 8). SMB: Command Reference. Retrieved July 17, 2020. 

  6. Nicolas Verdier. (n.d.). Retrieved January 29, 2018. 

  7. Microsoft. (n.d.). Netstat. Retrieved April 17, 2016. 

  8. Yonathan Klijnsma. (2016, May 17). Mofang: A politically motivated information stealing adversary. Retrieved May 12, 2020. 

  9. Savill, J. (1999, March 4). Net.exe reference. Retrieved September 22, 2015. 

  10. Schroeder, W., Warner, J., Nelson, M. (n.d.). Github PowerShellEmpire. Retrieved April 28, 2016. 

  11. BishopFox. (n.d.). Sliver Netstat. Retrieved September 16, 2021. 

  12. Nettitude. (2018, July 23). Python Server for PoshC2. Retrieved April 23, 2019. 

  13. Symantec Security Response Attack Investigation Team. (2018, April 23). New Orangeworm attack group targets the healthcare sector in the U.S., Europe, and Asia. Retrieved May 8, 2018. 

  14. Trend Micro. (2017, February 27). RATANKBA: Delving into Large-scale Watering Holes against Enterprises. Retrieved May 22, 2018. 

  15. Kamluk, V. & Gostev, A. (2016, February). Adwind - A Cross-Platform RAT. Retrieved April 23, 2019. 

  16. Roccio, T., et al. (2021, April). Technical Analysis of Cuba Ransomware. Retrieved June 18, 2021. 

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

  18. BI.ZONE Cyber Threats Research Team. (2021, May 13). From pentest to APT attack: cybercriminal group FIN7 disguises its malware as an ethical hacker’s toolkit. Retrieved February 2, 2022. 

  19. ESET Research. (2019, May 22). A journey to Zebrocy land. Retrieved June 20, 2019. 

  20. Falcone, R. and Wartell, R.. (2015, July 27). Observations on CVE-2015-3113, Prior Zero-Days and the Pirpi Payload. Retrieved January 22, 2016. 

  21. Sardiwal, M, et al. (2017, December 7). New Targeted Attack in the Middle East by APT34, a Suspected Iranian Threat Group, Using CVE-2017-11882 Exploit. Retrieved December 20, 2017. 

  22. Kaspersky Lab’s Global Research and Analysis Team. (2014, August 7). The Epic Turla Operation: Solving some of the mysteries of Snake/Uroburos. Retrieved December 11, 2014. 

  23. Kaspersky Lab’s Global Research & Analysis Team. (2014, August 06). The Epic Turla Operation: Solving some of the mysteries of Snake/Uroboros. Retrieved November 7, 2018. 

  24. Leong, R., Perez, D., Dean, T. (2019, October 31). MESSAGETAP: Who’s Reading Your Text Messages?. Retrieved May 11, 2020. 

  25. Blasco, J. (2011, December 12). Another Sykipot sample likely targeting US federal agencies. Retrieved March 28, 2016. 

  26. Secureworks. (2019, July 24). Updated Karagany Malware Targets Energy Sector. Retrieved August 12, 2020. 

  27. Yagi, J. (2014, August 24). Trojan.Volgmer. Retrieved July 16, 2018. 

  28. Beek, C. (2020, November 5). Operation North Star: Behind The Scenes. Retrieved December 20, 2021. 

  29. Baskin, B. (2020, July 8). TAU Threat Discovery: Conti Ransomware. Retrieved February 17, 2021. 

  30. Hada, H. (2021, December 28). Flagpro The new malware used by BlackTech. Retrieved March 25, 2022. 

  31. F-Secure Labs. (2014). BlackEnergy & Quedagh: The convergence of crimeware and APT attacks. Retrieved March 24, 2016. 

  32. Baumgartner, K. and Garnaeva, M.. (2014, November 3). BE2 custom plugins, router abuse, and target profiles. Retrieved March 24, 2016. 

  33. Hsu, K. et al. (2020, June 24). Lucifer: New Cryptojacking and DDoS Hybrid Malware Exploiting High and Critical Vulnerabilities to Infect Windows Devices. Retrieved November 16, 2020. 

  34. Biasini, N. et al.. (2022, January 21). Ukraine Campaign Delivers Defacement and Wipers, in Continued Escalation. Retrieved March 14, 2022. 

  35. Symantec Security Response. (2016, September 6). Buckeye cyberespionage group shifts gaze from US to Hong Kong. Retrieved September 26, 2016. 

  36. Computer Incident Response Center Luxembourg. (2013, March 29). Analysis of a PlugX variant. Retrieved November 5, 2018. 

  37. DHS/CISA, Cyber National Mission Force. (2020, October 1). Malware Analysis Report (MAR) MAR-10303705-1.v1 – Remote Access Trojan: SLOTHFULMEDIA. Retrieved October 2, 2020. 

  38. Nafisi, R., Lelli, A. (2021, March 4). GoldMax, GoldFinder, and Sibot: Analyzing NOBELIUM’s layered persistence. Retrieved March 8, 2021. 

  39. Check Point. (2022, January 11). APT35 exploits Log4j vulnerability to distribute new modular PowerShell toolkit. Retrieved January 24, 2022. 

  40. Mundo, A. et al. (2021, February). Technical Analysis of Babuk Ransomware. Retrieved August 11, 2021. 

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

  42. Su, V. et al. (2019, December 11). Waterbear Returns, Uses API Hooking to Evade Security. Retrieved February 22, 2021. 

  43. GovCERT. (2016, May 23). Technical Report about the Espionage Case at RUAG. Retrieved November 7, 2018. 

  44. Check Point Research. (2019, February 4). SpeakUp: A New Undetected Backdoor Linux Trojan. Retrieved April 17, 2019. 

  45. NHS Digital. (2020, November 26). Egregor Ransomware The RaaS successor to Maze. Retrieved December 29, 2020. 

  46. PwC and BAE Systems. (2017, April). Operation Cloud Hopper: Technical Annex. Retrieved April 13, 2017. 

  47. Antiy CERT. (2020, April 20). Analysis of Ramsay components of Darkhotel’s infiltration and isolation network. Retrieved March 24, 2021. 

  48. Chen, J.. (2020, May 12). Tropic Trooper’s Back: USBferry Attack Targets Air gapped Environments. Retrieved May 20, 2020. 

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

  50. Hromcova, Z. (2019, July). OKRUM AND KETRICAN: AN OVERVIEW OF RECENT KE3CHANG GROUP ACTIVITY. Retrieved May 6, 2020. 

  51. Mundo, A. (2020, March 26). Ransomware Maze. Retrieved May 18, 2020. 

  52. ESET. (2019, July). MACHETE JUST GOT SHARPER Venezuelan government institutions under attack. Retrieved September 13, 2019. 

  53. Symantec Security Response. (2011, November). W32.Duqu: The precursor to the next Stuxnet. Retrieved September 17, 2015. 

  54. Threat Intelligence Team. (2021, August 23). New variant of Konni malware used in campaign targetting Russia. Retrieved January 5, 2022. 

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

  56. Konstantin Zykov. (2019, September 23). Hello! My name is Dtrack. Retrieved January 20, 2021. 

  57. Mercer, W., Rascagneres, P. (2018, April 26). GravityRAT - The Two-Year Evolution Of An APT Targeting India. Retrieved May 16, 2018. 

  58. Grunzweig, J. (2018, January 31). Comnie Continues to Target Organizations in East Asia. Retrieved June 7, 2018. 

  59. Maniath, S. and Kadam P. (2019, March 19). Dissecting a NETWIRE Phishing Campaign’s Usage of Process Hollowing. Retrieved January 7, 2021. 

  60. Dahan, A. (2017). Operation Cobalt Kitty. Retrieved December 27, 2018. 

  61. Peretz, A. and Theck, E. (2021, March 5). Earth Vetala – MuddyWater Continues to Target Organizations in the Middle East. Retrieved March 18, 2021. 

  62. Jansen, W . (2021, January 12). Abusing cloud services to fly under the radar. Retrieved January 19, 2021. 

  63. 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. 

  64. Counter Threat Unit Research Team. (2017, June 27). BRONZE UNION Cyberespionage Persists Despite Disclosures. Retrieved July 13, 2017. 

  65. FireEye. (2018, October 03). APT38: Un-usual Suspects. Retrieved November 6, 2018. 

  66. 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. 

  67. Smallridge, R. (2018, March 10). APT15 is alive and strong: An analysis of RoyalCli and RoyalDNS. Retrieved April 4, 2018. 

  68. Scott W. Brady. (2020, October 15). United States vs. Yuriy Sergeyevich Andrienko et al.. Retrieved November 25, 2020. 

  69. Joe Slowik. (2018, October 12). Anatomy of an Attack: Detecting and Defeating CRASHOVERRIDE. Retrieved December 18, 2020. 

  70. Kaspersky Lab’s Global Research and Analysis Team. (2016, February 9). Poseidon Group: a Targeted Attack Boutique specializing in global cyber-espionage. Retrieved March 16, 2016. 

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

  72. Cybereason Nocturnus. (2019, June 25). Operation Soft Cell: A Worldwide Campaign Against Telecommunications Providers. Retrieved July 18, 2019. 

  73. 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. 

  74. Yates, M. (2017, June 18). APT3 Uncovered: The code evolution of Pirpi. Retrieved September 28, 2017. 

  75. Fraser, N., et al. (2019, August 7). Double DragonAPT41, a dual espionage and cyber crime operation APT41. Retrieved September 23, 2019. 

  76. Rostovcev, N. (2021, June 10). Big airline heist APT41 likely behind a third-party attack on Air India. Retrieved August 26, 2021. 

  77. Falcone, R. and Lee, B.. (2016, May 26). The OilRig Campaign: Attacks on Saudi Arabian Organizations Deliver Helminth Backdoor. Retrieved May 3, 2017. 

  78. Vyacheslav Kopeytsev and Seongsu Park. (2021, February 25). Lazarus targets defense industry with ThreatNeedle. Retrieved October 27, 2021. 

  79. Faou, M. (2020, May). From Agent.btz to ComRAT v4: A ten-year journey. Retrieved June 15, 2020. 

  80. Faou, M. and Dumont R.. (2019, May 29). A dive into Turla PowerShell usage. Retrieved June 14, 2019. 

  81. PwC and BAE Systems. (2017, April). Operation Cloud Hopper. Retrieved April 5, 2017. 

  82. Fiser, D. Oliveira, A. (n.d.). Tracking the Activities of TeamTNT A Closer Look at a Cloud-Focused Malicious Actor Group. Retrieved September 22, 2021. 

  83. AT&T Alien Labs. (2021, September 8). TeamTNT with new campaign aka Chimaera. Retrieved September 22, 2021. 

  84. 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. 

  85. Hamzeloofard, S. (2020, January 31). New wave of PlugX targets Hong Kong | Avira Blog. Retrieved April 13, 2021. 

  86. Mandiant. (n.d.). APT1 Exposing One of China’s Cyber Espionage Units. Retrieved July 18, 2016. 

  87. Park, S. (2021, June 15). Andariel evolves to target South Korea with ransomware. Retrieved September 29, 2021. 

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