t1563-001-ssh-hijacking

name	T1563.001_ssh-hijacking
description	Adversaries may hijack a legitimate user's SSH session to move laterally within an environment.
category	authorization
version	18.1
author	cyberstrike-official
tags	["mitre-attack","enterprise","t1563.001","lateral-movement","linux","macos","sub-technique"]
technique_id	T1563.001
tactic	lateral-movement
all_tactics	["lateral-movement"]
platforms	["Linux","macOS"]
mitre_url	https://attack.mitre.org/techniques/T1563/001
tech_stack	["linux","macos"]
cwe_ids	["CWE-284"]
chains_with	["T1563","T1563.002"]
prerequisites	["T1563"]
severity_boost	{"T1563":"Chain with T1563 for deeper attack path","T1563.002":"Chain with T1563.002 for deeper attack path"}

T1563.001 SSH Hijacking

Sub-technique of: T1563

High-Level Description

Adversaries may hijack a legitimate user's SSH session to move laterally within an environment. Secure Shell (SSH) is a standard means of remote access on Linux and macOS systems. It allows a user to connect to another system via an encrypted tunnel, commonly authenticating through a password, certificate or the use of an asymmetric encryption key pair.

In order to move laterally from a compromised host, adversaries may take advantage of trust relationships established with other systems via public key authentication in active SSH sessions by hijacking an existing connection to another system. This may occur through compromising the SSH agent itself or by having access to the agent's socket. If an adversary is able to obtain root access, then hijacking SSH sessions is likely trivial.

SSH Hijacking differs from use of SSH because it hijacks an existing SSH session rather than creating a new session using Valid Accounts.

Kill Chain Phase

• Lateral Movement (TA0008)

Platforms: Linux, macOS

What to Check

• Identify if SSH Hijacking technique is applicable to target environment
• Check Linux systems for indicators of SSH Hijacking
• Check macOS systems for indicators of SSH Hijacking
• Verify mitigations are bypassed or absent (4 known mitigations)
• Assess detection coverage (1 detection strategies)

How to Test

Manual Testing

1. Identify Attack Surface: Determine if the target environment is susceptible to SSH Hijacking by examining the target platforms (Linux, macOS).

2. Assess Existing Defenses: Review whether mitigations for T1563.001 are in place. If defenses are absent or misconfigured, this technique may be exploitable.

3. Execute Test: Use tools and methods described in the MITRE ATT&CK page and external references below.

Note: No Atomic Red Team tests available for this technique. See Atomic Red Team GitHub for updates.

Remediation Guide

M1022 Restrict File and Directory Permissions