System Owner/User Discovery
|System Owner/User Discovery|
|Platform||Linux, macOS, Windows|
|Permissions Required||User, Administrator|
|Data Sources||File monitoring, Process monitoring, Process command-line parameters|
Adversaries may attempt to identify the primary user, currently logged in user, set of users that commonly uses a system, or whether a user is actively using the system. They may do this, for example, by retrieving account usernames or by using Credential Dumping. The information may be collected in a number of different ways using other Discovery techniques, because user and username details are prevalent throughout a system and include running process ownership, file/directory ownership, session information, and system logs.
On Mac, the currently logged in user can be identified with
On Linux, the currently logged in user can be identified with
- APT28 has queried information on machines to determine the current user or system owner 1.
- An APT3 downloader uses the Windows command
"cmd.exe" /C whoamito verify that it is running with the elevated privileges of “System.”2
- FIN10 has used Meterpreter to enumerate users on remote systems.3
- A Gamaredon Group file stealer can gather the victim's username to send to a C2 server.4
- Lazarus Group malware SierraAlfa and WhiskeyAlfa-Three enumerate logged-on users. Lazarus Group malware IndiaIndia collects the victim's username and sends it to the C2 server.5 67
- Magic Hound malware has obtained the victim username and sent it to the C2 server.8
- OilRig has run
whoamion a victim.910
- Patchwork collected the victim username and whether it was running as admin, then sent the information to its C2 server.11
- Stealth Falcon malware gathers the registered user and primary owner name via WMI.12
- Agent.btz obtains the victim username and saves it to a file.13
- Backdoor.Oldrea collects the current username from the victim.14
- A Linux version of Derusbi checks if the victim user ID is anything other than zero (normally used for root), and the malware will not execute if it does not have root privileges.15
- DownPaper collects the victim username and sends it to the C2 server.16
- Felismus collects the current username and sends it to the C2 server.17
- Gazer obtains the current user's security identifier.18
- The OsInfo function in Komplex collects the current running username.19
- Mis-Type runs tests to determine the privilege level of the compromised user.20
- MoonWind obtains the victim username.21
- POWRUNER may collect information about the currently logged in user by running
whoamion a victim.22
- PowerDuke has commands to get the current user's name and SID.23
- A module in Prikormka collects information from the victim about the current user name.24
- RTM can obtain the victim username and permissions.25
- Reaver collects the victim's username.26
- RedLeaves can obtain information about the logged on user both locally and for Remote Desktop sessions.27
- Remsec can obtain information about the current user.28
- SslMM sends the logged-on username to its hard-coded C2.29
- Sys10 collects the account name of the logged-in user and sends it to the C2.29
- T9000 gathers and beacons the username of the logged in account during installation. It will also gather the username of running processes to determine if it is running as SYSTEM.30
- Unknown Logger can obtain information about the victim usernames.31
- WINDSHIELD can gather the victim user name.32
- WinMM uses NetUser-GetInfo to identify that it is running under an “Admin” account on the local system.29
- XAgentOSX contains the getInfoOSX function to return the OS X version as well as the current user.1
Identify unnecessary system utilities or potentially malicious software that may be used to acquire information about system users, and audit and/or block them by using whitelisting33 tools, like AppLocker,3435 or Software Restriction Policies36 where appropriate.37
System and network discovery techniques normally occur throughout an operation as an adversary learns the environment. Data and events should not be viewed in isolation, but as part of a chain of behavior that could lead to other activities based on the information obtained.
Monitor processes and command-line arguments for actions that could be taken to gather system and network information. Remote access tools with built-in features may interact directly with the Windows API to gather information. Information may also be acquired through Windows system management tools such as Windows Management Instrumentation and PowerShell.
- Robert Falcone. (2017, February 14). XAgentOSX: Sofacy's Xagent macOS Tool. Retrieved July 12, 2017.
- Moran, N., et al. (2014, November 21). Operation Double Tap. Retrieved January 14, 2016.
- FireEye iSIGHT Intelligence. (2017, June 16). FIN10: Anatomy of a Cyber Extortion Operation. Retrieved June 25, 2017.
- Kasza, A. and Reichel, D.. (2017, February 27). The Gamaredon Group Toolset Evolution. Retrieved March 1, 2017.
- Novetta Threat Research Group. (2016, February 24). Operation Blockbuster: Loaders, Installers and Uninstallers Report. Retrieved March 2, 2016.
- Novetta Threat Research Group. (2016, February 24). Operation Blockbuster: Remote Administration Tools & Content Staging Malware Report. Retrieved March 16, 2016.
- Novetta Threat Research Group. (2016, February 24). Operation Blockbuster: Destructive Malware Report. Retrieved March 2, 2016.
- Lee, B. and Falcone, R. (2017, February 15). Magic Hound Campaign Attacks Saudi Targets. Retrieved December 27, 2017.
- Falcone, R. and Lee, B.. (2016, May 26). The OilRig Campaign: Attacks on Saudi Arabian Organizations Deliver Helminth Backdoor. Retrieved May 3, 2017.
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- Cymmetria. (2016). Unveiling Patchwork - The Copy-Paste APT. Retrieved August 3, 2016.
- 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.
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- Symantec Security Response. (2014, July 7). Dragonfly: Cyberespionage Attacks Against Energy Suppliers. Retrieved April 8, 2016.
- Fidelis Cybersecurity. (2016, February 29). The Turbo Campaign, Featuring Derusbi for 64-bit Linux. Retrieved March 2, 2016.
- ClearSky Cyber Security. (2017, December). Charming Kitten. Retrieved December 27, 2017.
- Somerville, L. and Toro, A. (2017, March 30). Playing Cat & Mouse: Introducing the Felismus Malware. Retrieved November 16, 2017.
- Kaspersky Lab's Global Research & Analysis Team. (2017, August 30). Introducing WhiteBear. Retrieved September 21, 2017.
- Dani Creus, Tyler Halfpop, Robert Falcone. (2016, September 26). Sofacy's 'Komplex' OS X Trojan. Retrieved July 8, 2017.
- Gross, J. (2016, February 23). Operation Dust Storm. Retrieved September 19, 2017.
- Miller-Osborn, J. and Grunzweig, J.. (2017, March 30). Trochilus and New MoonWind RATs Used In Attack Against Thai Organizations. Retrieved March 30, 2017.
- 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.
- Adair, S.. (2016, November 9). PowerDuke: Widespread Post-Election Spear Phishing Campaigns Targeting Think Tanks and NGOs. Retrieved January 11, 2017.
- Cherepanov, A.. (2016, May 17). Operation Groundbait: Analysis of a surveillance toolkit. Retrieved May 18, 2016.
- Faou, M. and Boutin, J.. (2017, February). Read The Manual: A Guide to the RTM Banking Trojan. Retrieved March 9, 2017.
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- PwC and BAE Systems. (2017, April). Operation Cloud Hopper: Technical Annex. Retrieved April 13, 2017.
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- Baumgartner, K., Golovkin, M.. (2015, May). The MsnMM Campaigns: The Earliest Naikon APT Campaigns. Retrieved December 17, 2015.
- Grunzweig, J. and Miller-Osborn, J.. (2016, February 4). T9000: Advanced Modular Backdoor Uses Complex Anti-Analysis Techniques. Retrieved April 15, 2016.
- Settle, A., et al. (2016, August 8). MONSOON - Analysis Of An APT Campaign. Retrieved September 22, 2016.
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- Beechey, J. (2010, December). Application Whitelisting: Panacea or Propaganda?. Retrieved November 18, 2014.
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