Remote Access Software
An adversary may use legitimate desktop support and remote access software, such as Team Viewer, Go2Assist, LogMein, AmmyyAdmin, etc, to establish an interactive command and control channel to target systems within networks. These services are commonly used as legitimate technical support software, and may be allowed by application control within a target environment. Remote access tools like VNC, Ammyy, and Teamviewer are used frequently when compared with other legitimate software commonly used by adversaries. [1]
Remote access tools may be established and used post-compromise as alternate communications channel for redundant access or as a way to establish an interactive remote desktop session with the target system. They may also be used as a component of malware to establish a reverse connection or back-connect to a service or adversary controlled system.
Admin tools such as TeamViewer have been used by several groups targeting institutions in countries of interest to the Russian state and criminal campaigns. [2] [3]
Procedure Examples
| Name | Description |
|---|---|
| Carbanak | |
| Carbanak |
Carbanak used legitimate programs such as AmmyyAdmin and Team Viewer for remote interactive C2 to target systems.[12] |
| Cobalt Group |
Cobalt Group used the Ammyy Admin tool as well as TeamViewer for remote access, including to preserve remote access if a Cobalt Strike module was lost.[8][9][10] |
| DarkVishnya |
DarkVishnya used DameWare Mini Remote Control for lateral movement.[15] |
| Dridex | |
| Kimsuky |
Kimsuky has used a modified TeamViewer client as a command and control channel.[13] |
| Night Dragon |
Night Dragon has used several remote administration tools as persistent infiltration channels.[11] |
| RTM |
RTM has the capability to download a VNC module from command and control (C2).[6] |
| RTM |
RTM has used a modified version of TeamViewer and Remote Utilities for remote access.[14] |
| Sandworm Team |
Sandworm Team has used remote administration tools or remote industrial control system client software to maliciously release electricity breakers.[16] |
| Thrip |
Thrip used a cloud-based remote access software called LogMeIn for their attacks.[7] |
Mitigations
| Mitigation | Description |
|---|---|
| Execution Prevention |
Use application control to mitigate installation and use of unapproved software that can be used for remote access. |
| Filter Network Traffic |
Properly configure firewalls, application firewalls, and proxies to limit outgoing traffic to sites and services used by remote access tools. |
| Network Intrusion Prevention |
Network intrusion detection and prevention systems that use network signatures may be able to prevent traffic to remote access services. |
Detection
Monitor for applications and processes related to remote admin tools. Correlate activity with other suspicious behavior that may reduce false positives if these tools are used by legitimate users and administrators.
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 for the port that is being used.
Domain Fronting may be used in conjunction to avoid defenses. Adversaries will likely need to deploy and/or install these remote tools to compromised systems. It may be possible to detect or prevent the installation of these tools with host-based solutions.
References
- Wueest, C., Anand, H. (2017, July). Living off the land and fileless attack techniques. Retrieved April 10, 2018.
- CrowdStrike Intelligence. (2016). 2015 Global Threat Report. Retrieved April 11, 2018.
- CrySyS Lab. (2013, March 20). TeamSpy – Obshie manevri. Ispolzovat’ tolko s razreshenija S-a. Retrieved April 11, 2018.
- Bennett, J., Vengerik, B. (2017, June 12). Behind the CARBANAK Backdoor. Retrieved June 11, 2018.
- Dell SecureWorks Counter Threat Unit Threat Intelligence. (2015, October 13). Dridex (Bugat v5) Botnet Takeover Operation. Retrieved May 31, 2019.
- Faou, M. and Boutin, J. (2017, February). Read The Manual: A Guide to the RTM Banking Trojan. Retrieved March 9, 2017.
- Security Response Attack Investigation Team. (2018, June 19). Thrip: Espionage Group Hits Satellite, Telecoms, and Defense Companies. Retrieved July 10, 2018.
- Positive Technologies. (2017, August 16). Cobalt Strikes Back: An Evolving Multinational Threat to Finance. Retrieved September 5, 2018.
- Positive Technologies. (2016, December 16). Cobalt Snatch. Retrieved October 9, 2018.
- Matveeva, V. (2017, August 15). Secrets of Cobalt. Retrieved October 10, 2018.
- McAfee® Foundstone® Professional Services and McAfee Labs™. (2011, February 10). Global Energy Cyberattacks: “Night Dragon”. Retrieved February 19, 2018.
- Group-IB and Fox-IT. (2014, December). Anunak: APT against financial institutions. Retrieved April 20, 2016.
- Tarakanov , D.. (2013, September 11). The “Kimsuky” Operation: A North Korean APT?. Retrieved August 13, 2019.
- Skulkin, O. (2019, August 5). Following the RTM Forensic examination of a computer infected with a banking trojan. Retrieved May 11, 2020.
- Golovanov, S. (2018, December 6). DarkVishnya: Banks attacked through direct connection to local network. Retrieved May 15, 2020.
- US-CERT. (2016, February 25). ICS Alert (IR-ALERT-H-16-056-01) Cyber-Attack Against Ukrainian Critical Infrastructure. Retrieved June 10, 2020.