Skip to content

T1611 Escape to Host

Adversaries may break out of a container to gain access to the underlying host. This can allow an adversary access to other containerized resources from the host level or to the host itself. In principle, containerized resources should provide a clear separation of application functionality and be isolated from the host environment.1

There are multiple ways an adversary may escape to a host environment. Examples include creating a container configured to mount the host’s filesystem using the bind parameter, which allows the adversary to drop payloads and execute control utilities such as cron on the host, or utilizing a privileged container to run commands on the underlying host.234 Adversaries may also escape via Exploitation for Privilege Escalation, such as exploiting vulnerabilities in global symbolic links in order to access the root directory of a host machine.5

Gaining access to the host may provide the adversary with the opportunity to achieve follow-on objectives, such as establishing persistence, moving laterally within the environment, or setting up a command and control channel on the host.

Item Value
ID T1611
Sub-techniques
Tactics TA0004
Platforms Containers, Linux, Windows
Permissions required Administrator, User, root
Version 1.2
Created 30 March 2021
Last Modified 01 April 2022

Procedure Examples

ID Name Description
S0600 Doki Doki’s container was configured to bind the host root directory.4
S0601 Hildegard Hildegard has used the BOtB tool that can break out of containers. 9
S0683 Peirates Peirates can gain a reverse shell on a host node by mounting the Kubernetes hostPath.7
S0623 Siloscape Siloscape maps the host’s C drive to the container by creating a global symbolic link to the host through the calling of NtSetInformationSymbolicLink.8
G0139 TeamTNT TeamTNT has deployed privileged containers that mount the filesystem of victim machine.1011

Mitigations

ID Mitigation Description
M1048 Application Isolation and Sandboxing Consider utilizing seccomp, seccomp-bpf, or a similar solution that restricts certain system calls such as mount. In Kubernetes environments, consider defining a Pod Security Policy that limits container access to host process namespaces, the host network, and the host file system.6
M1038 Execution Prevention Use read-only containers, read-only file systems, and minimal images when possible to prevent the running of commands.6
M1026 Privileged Account Management Ensure containers are not running as root by default. In Kubernetes environments, consider defining a Pod Security Policy that prevents pods from running privileged containers.6

Detection

ID Data Source Data Component
DS0032 Container Container Creation
DS0009 Process OS API Execution
DS0034 Volume Volume Modification

References

  1. Docker. (n.d.). Docker Overview. Retrieved March 30, 2021. ↩

  2. Docker. (n.d.). Use Bind Mounts. Retrieved March 30, 2021. ↩

  3. Fiser, D., Oliveira, A.. (2019, December 20). Why a Privileged Container in Docker is a Bad Idea. Retrieved March 30, 2021. ↩

  4. Fishbein, N., Kajiloti, M.. (2020, July 28). Watch Your Containers: Doki Infecting Docker Servers in the Cloud. Retrieved March 30, 2021. ↩↩

  5. Daniel Prizmant. (2020, July 15). Windows Server Containers Are Open, and Here’s How You Can Break Out. Retrieved October 1, 2021. ↩

  6. National Security Agency, Cybersecurity and Infrastructure Security Agency. (2022, March). Kubernetes Hardening Guide. Retrieved April 1, 2022. ↩↩↩

  7. InGuardians. (2022, January 5). Peirates GitHub. Retrieved February 8, 2022. ↩

  8. Prizmant, D. (2021, June 7). Siloscape: First Known Malware Targeting Windows Containers to Compromise Cloud Environments. Retrieved June 9, 2021. ↩

  9. Chen, J. et al. (2021, February 3). Hildegard: New TeamTNT Cryptojacking Malware Targeting Kubernetes. Retrieved April 5, 2021. ↩

  10. Fishbein, N. (2020, September 8). Attackers Abusing Legitimate Cloud Monitoring Tools to Conduct Cyber Attacks. Retrieved September 22, 2021. ↩

  11. Kol, Roi. Morag, A. (2020, August 25). Deep Analysis of TeamTNT Techniques Using Container Images to Attack. Retrieved September 22, 2021. ↩

  12. FBI. (2020, November 19). Indicators of Compromise Associated with Ragnar Locker Ransomware. Retrieved April 1, 2021. ↩

Back to top