Remote Service Session Hijacking

Adversaries may take control of preexisting sessions with remote services to move laterally in an environment. Users may use valid credentials to log into a service specifically designed to accept remote connections, such as telnet, SSH, and RDP. When a user logs into a service, a session will be established that will allow them to maintain a continuous interaction with that service.

Adversaries may commandeer these sessions to carry out actions on remote systems. Remote Service Session Hijacking differs from use of Remote Services because it hijacks an existing session rather than creating a new session using Valid Accounts.[1][2]

ID: T1563
Sub-techniques:  T1563.001, T1563.002
Tactic: Lateral Movement
Platforms: Linux, Windows, macOS
Permissions Required: SYSTEM, root
Data Sources: Authentication logs, Netflow/Enclave netflow, Process command-line parameters, Process monitoring
Version: 1.0
Created: 25 February 2020
Last Modified: 23 March 2020

Mitigations

Mitigation Description
Disable or Remove Feature or Program

Disable the remote service (ex: SSH, RDP, etc.) if it is unnecessary.

Network Segmentation

Enable firewall rules to block unnecessary traffic between network security zones within a network.

Privileged Account Management

Do not allow remote access to services as a privileged account unless necessary.

User Account Management

Limit remote user permissions if remote access is necessary.

Detection

Use of these services may be legitimate, depending upon the network environment and how it is used. Other factors, such as access patterns and activity that occurs after a remote login, may indicate suspicious or malicious behavior with that service. Monitor for user accounts logged into systems they would not normally access or access patterns to multiple systems over a relatively short period of time.

Monitor for processes and command-line arguments associated with hijacking service sessions.

References