Lateral Movement

Lateral movement refers to techniques with which attackers work their way from system to system through a network after the initial breach. The goal is to expand privileges, find sensitive data, and ultimately bring critical systems under control.

The first break-in to a network is rarely the actual goal for attackers. A compromised office PC or a captured password is of little value at first. The major damage arises afterward: when attackers work their way unnoticed from system to system, gain administrator rights, and finally reach databases, backups, or production control systems.

This phase is called lateral movement. It determines whether a limited incident becomes a company-wide emergency. Anyone who understands lateral movement and impedes it takes away a large part of the impact from attacks such as ransomware.

What is lateral movement?

Lateral movement refers to all the techniques with which attackers spread within an already compromised network. The term describes the direction of the approach: after the initial access, the attacker moves sideways through the environment, from a relatively unimportant entry point to ever more valuable targets.

Typical is the combination of reconnaissance and privilege escalation. On every system they reach, attackers gather information and credentials with which to take the next step. Modern attack groups prefer to use legitimate administration tools and regular logins for this. This approach is called Living off the Land and is hard for traditional protection software to detect, because no obvious malicious code is executed.

The MITRE ATT&CK framework lists lateral movement as a tactic of its own with documented techniques, including the use of remote desktop connections, administrative shares, and stolen authentication tickets.

How it works

A typical attack follows a recurring pattern:

1. Network reconnaissance: From the first compromised system, the attacker examines the environment: which systems are reachable, which services are running, where are shares and directory services? 1. Theft of credentials: From memory, from configuration files, or via extracted password hashes, the attacker obtains further login data, ideally those of an administrator. 1. Login to the next system: With the captured credentials, the attacker logs in normally to further systems, often via remote desktop, administrative shares, or remote maintenance tools. 1. Privilege escalation: On every new system, the attacker looks for ways to higher privileges, up to the central administration of the entire environment. 1. Repetition until the goal: These steps repeat until the actual goal is reached: sensitive databases, central file stores, backup systems, or the infrastructure for widespread distribution of ransomware.

Two conditions make this approach so effective: flat networks in which almost every system can reach every other one, and generously assigned permissions that make every captured account valuable.

Why it matters

This is where the extent of the damage is decided: whether an incident affects a single machine or paralyzes the whole company depends above all on how far the attacker was able to spread.
Ransomware needs reach: extortion groups want to encrypt as many systems as possible at the same time, including the backups. Without lateral movement, their leverage stays small.
Attacks stay undetected for a long time: attackers often remain in networks for weeks before they strike. During this time, lateral movement in particular takes place, which is hardly noticeable without appropriate controls.
Legitimate tools disguise the attack: because attackers use regular logins and existing administration tools, purely signature-based protection mechanisms fall short. What stands out above all is communication between systems that have nothing to do with each other functionally.
Compliance demands containment: frameworks such as NIS2 and ISO 27001 require measures that limit the spread of incidents. Evidence is provided through segmentation and controlled internal communication.

Typical use cases

Ransomware in mid-sized companies: after a phishing email, the attacker takes over a workstation, captures administrator access, and encrypts servers and backups at the same time weeks later. The path to that point consists almost entirely of lateral movement.
Production and OT: if an attacker gets from the office network into the production network, downtime and physical damage loom. The transitions between IT and OT are therefore the most important place to stop lateral movement.
Hospitals and critical infrastructure: medical devices and administrative systems historically often share the same network. Attackers use this proximity to advance from inconspicuous systems to patient-critical ones.
Compromised remote access: a captured VPN account, for example that of a service provider, often opens up the view onto large network areas. From there, the systematic spread toward central systems begins.

Lateral movement and initial access: the difference

Initial access is the moment when attackers first get into a network, for example via phishing, an unpatched vulnerability, or purchased credentials. Lateral movement begins afterward: it covers everything attackers do to spread from the entry point and expand their position.

For defenders, this distinction is central, because both phases require different countermeasures. Initial access is made harder by email security, patch management, multi-factor authentication, and the protection of publicly reachable applications, for example through a Web Application Firewall . Against lateral movement, segmentation, restrictively assigned permissions, and monitoring of internal connections help.

Experience shows that initial access can never be fully prevented. A resilient security strategy accepts this and ensures that a single compromised machine has no consequences. This is exactly where Zero Trust concepts and microsegmentation come in.

Protection with KAEMI

KAEMI helps companies make lateral movement visible and contain it effectively. With Zero Trust Microsegmentation based on Illumio, we visualize the communication between your systems and enforce policies that take away attackers' sideways movement. In addition, Zero Trust Network Access limits remote access to individual applications rather than to the entire network. We would be glad to show you in a conversation how the two work together in your environment.

Frequently asked questions about Lateral Movement

How do companies detect lateral movement in their own network?

What stands out are connections between systems that have nothing to do with each other functionally, logins at unusual times, and the sudden use of administrative tools on normal workstations. The prerequisite is visibility: anyone who does not observe internal communication usually notices the spread only at the point of encryption. Microsegmentation tools provide a map of all communication relationships for this purpose.

What role does lateral movement play in ransomware?

A central one. Modern ransomware groups rarely encrypt only the first infected machine. They first spread, take over central administration systems, and disable backups. Only when enough systems are under control does encryption start everywhere at the same time. Anyone who stops the spread early prevents the widespread standstill and keeps functioning recovery points.

Does a virus scanner prevent lateral movement?

Only to a limited extent. For spreading, attackers prefer to use legitimate credentials and existing administration tools, that is activities that initially look normal to endpoint protection. Endpoint solutions detect parts of the approach, such as the extraction of credentials. More effective is the combination: endpoint protection plus segmentation, restrictive permissions, and multi-factor authentication, so that captured accounts have as little reach as possible.

What is the most effective protection against lateral movement?

Segmentation achieves the greatest effect: when systems are allowed to communicate only with the counterparts they need functionally, attackers lose their freedom of movement. In addition, multi-factor authentication, sparingly assigned administrator rights, and separate accounts for administrative tasks help. Microsegmentation implements this control down to individual servers and applications and is therefore regarded as a core building block of Zero Trust architectures.

Does lateral movement affect cloud environments too?

Yes. In the cloud, attackers move via compromised access keys, overly broad roles, and connections between services. The principle stays the same. Hybrid environments are particularly affected, because attackers can switch between the data center and the cloud. Uniform policies for permissions and communication across all environments are therefore an important part of the defense.