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MITRE ATT&CK® ICS Asset

A0016: Firewall

A gateway that limits access between networks in accordance with local security policy.

In ICS networks, firewalls can exist in multiple locations in the network architecture and serve a variety of purposes. The first, and often the most important, is the firewall segmenting the ICS network from the business network. This firewall acts as the primary network boundary point that controls the ingress/egress of network traffic between the ICS and business networks. This firewall may also be a single device connected to multiple network segments, where the firewall defines individual zones for the different network segments and can control access to the zones and between the zones. This can limit the ability of an adversary to traverse a network.

ICSA0016ICS AssetObject v1.1 Modified
Discuss defensive coverage Back to ATT&CK
Glexia's Take

Analyst context for executives and security teams

Analyst confidence Medium

In an ICS environment, a firewall is often the control point that separates business IT from control system networks and enforces traffic between zones. Its value is not just blocking traffic; it is a dependency for operational resilience because many ATT&CK techniques target it as a path for access, discovery, remote administration, evasion, command and control, or disruption. Executives should treat firewall governance as both a security and continuity issue: if rules, remote access paths, credentials, or logging are weak, defenders may lose visibility into the boundary that is meant to limit adversary movement into industrial operations.

Executive priority

Prioritize evidence that ICS firewalls are intentionally segmented, governed by local security policy, monitored, and included in incident response planning. This asset is related to techniques involving public-facing application exploitation, external remote services, valid accounts, discovery, network sniffing, adversary-in-the-middle activity, denial of service, device restart/shutdown, and data destruction. That relationship context makes firewall control assurance relevant to business continuity, vendor/remote access risk, vulnerability prioritization, audit evidence, and cyber-physical risk management. Leaders should ask who owns rule approval, how emergency changes are reviewed, what remote access is permitted, whether logs are retained centrally, and whether operations can continue if the firewall becomes unavailable or misconfigured.

Technical view

For SOC, detection engineering, and IR teams, validate the firewall as a monitored ICS boundary asset across Embedded, Windows, Linux, and Network platforms where applicable. ATT&CK provides no official detection text for this asset, so coverage should be derived from its role and related techniques: command-line or GUI administration, external remote services, valid-account use, public-facing exposure, remote service exploitation, network discovery, port/broadcast/multicast discovery, standard application-layer protocols, network sniffing, adversary-in-the-middle conditions, evasion through exploitation, indicator removal, restart/shutdown, denial of service, and destructive activity. Confirm that firewall management events, rule changes, authentication events, interface status, traffic denies/allows, remote administration sessions, and anomalous protocol flows are available to investigators before an incident.

Likely telemetry

  • Firewall allow/deny traffic logs across ICS-to-business and inter-zone boundaries
  • Firewall rule, policy, NAT, route, and object change records
  • Administrator authentication, authorization, session, CLI, and GUI access logs
  • Remote access and external remote service connection records where the firewall participates in access control
  • System health telemetry such as interface state, CPU/memory, restart/shutdown events, and service availability

Detection direction

  • Baseline expected traffic between the business network, ICS network, and internal firewall zones; alert on new paths, unusual protocols, and unexpected ingress/egress patterns.
  • Monitor administrative access for unusual source locations, times, accounts, failed logons, successful privileged sessions, and changes made through CLI or GUI interfaces.
  • Tune discovery detections for port scanning, broadcast discovery, and multicast discovery with awareness that legitimate engineering, inventory, and monitoring tools may generate similar traffic.
  • Correlate firewall events with remote access, valid-account use, public-facing service exposure, and exploitation-related vulnerability evidence to improve triage value.
  • Watch for loss of visibility signals: logging disabled, configuration changes without approval, indicator removal behavior, unexpected restart/shutdown, interface flaps, or denial-of-service symptoms.

Mitigation priorities

  • Establish and document the firewall’s intended role as the ICS/business boundary and, where applicable, as an inter-zone control point.
  • Maintain least-privilege rule sets that allow only required communications between ICS, business, vendor, and management zones.
  • Restrict and monitor administrative access, including CLI, GUI, and remote service access; review default, shared, and privileged accounts.
  • Include firewall software, firmware, public-facing services, and remote access components in vulnerability and patch prioritization based on exposure and operational criticality.
  • Centralize logs, preserve configuration history, and test that logs remain available during incident response.
Analyst notes and limits

This take is based on the ATT&CK ICS asset A0016 Firewall and the supplied relationships showing many ICS techniques targeting this asset. The object is an asset, not a technique, and ATT&CK lists no tactics and no official detection guidance. The most defensible use of this object is to drive control validation: segmentation, remote access governance, administrative monitoring, vulnerability exposure review, and IR readiness for a critical ICS boundary device.

ATT&CK does not provide official detection content for this asset, and the supplied relationships do not prove that any specific environment is exposed, compromised, or monitored. Local architecture, firewall product capabilities, rule sets, remote access design, logging configuration, and operational safety requirements are required to determine actual risk and coverage.

Official MITRE ATT&CK definition

Firewall

A gateway that limits access between networks in accordance with local security policy.

In ICS networks, firewalls can exist in multiple locations in the network architecture and serve a variety of purposes. The first, and often the most important, is the firewall segmenting the ICS network from the business network. This firewall acts as the primary network boundary point that controls the ingress/egress of network traffic between the ICS and business networks. This firewall may also be a single device connected to multiple network segments, where the firewall defines individual zones for the different network segments and can control access to the zones and between the zones. This can limit the ability of an adversary to traverse a network.

View the same entry on attack.mitre.org (MITRE-hosted reference; in-page links above use the Glexia ATT&CK library.)

Glexia analysis

How security teams should use this page

Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.

ATT&CK relationship table

Techniques used

This mirrors the MITRE pattern of making group, software, campaign, and technique relationships scannable. Relationship notes come from mirrored ATT&CK relationship text when available.

39 rows
Domain ID Name Relationship / procedure
ICS T0872 Indicator Removal on Host Indicator Removal on Host targets this object.
ICS T0871 Execution through API Execution through API targets this object.
ICS T1695.002 Ethernet Sub-technique Ethernet targets this object.
ICS T0822 External Remote Services External Remote Services targets this object.
ICS T0814 Denial of Service Denial of Service targets this object.
ICS T0809 Data Destruction Data Destruction targets this object.
ICS T0820 Exploitation for Evasion Exploitation for Evasion targets this object.
ICS T0842 Network Sniffing Network Sniffing targets this object.
ICS T0893 Data from Local System Data from Local System targets this object.
ICS T0883 Internet Accessible Device Internet Accessible Device targets this object.
ICS T0823 Graphical User Interface Graphical User Interface targets this object.
ICS T0830 Adversary-in-the-Middle Adversary-in-the-Middle targets this object.
ICS T0881 Service Stop Service Stop targets this object.
ICS T1693.001 System Firmware Sub-technique System Firmware targets this object.
ICS T1695.003 Wi-Fi Sub-technique Wi-Fi targets this object.
ICS T0840 Network Connection Enumeration Network Connection Enumeration targets this object.
ICS T0892 Change Credential Change Credential targets this object.
ICS T0846.003 Multicast Discovery Sub-technique Multicast Discovery targets this object.
ICS T0859 Valid Accounts Valid Accounts targets this object.
ICS T0853 Scripting Scripting targets this object.
ICS T0890 Exploitation for Privilege Escalation Exploitation for Privilege Escalation targets this object.
ICS T0866 Exploitation of Remote Services Exploitation of Remote Services targets this object.
ICS T0862 Supply Chain Compromise Supply Chain Compromise targets this object.
ICS T0846.002 Broadcast Discovery Sub-technique Broadcast Discovery targets this object.
ICS T0885 Commonly Used Port Commonly Used Port targets this object.
ICS T1694.001 Default Credentials Sub-technique Default Credentials targets this object.
ICS T0834 Native API Native API targets this object.
ICS T0819 Exploit Public-Facing Application Exploit Public-Facing Application targets this object.
ICS T0884 Connection Proxy Connection Proxy targets this object.
ICS T1694 Insecure Credentials Insecure Credentials targets this object.
ICS T0851 Rootkit Rootkit targets this object.
ICS T0816 Device Restart/Shutdown Device Restart/Shutdown targets this object.
ICS T0846.001 Port Scan Sub-technique Port Scan targets this object.
ICS T0869 Standard Application Layer Protocol Standard Application Layer Protocol targets this object.
ICS T0807 Command-Line Interface Command-Line Interface targets this object.
ICS T1695 Block Communications Block Communications targets this object.
ICS T0874 Hooking Hooking targets this object.
ICS T0846 Remote System Discovery Remote System Discovery targets this object.
ICS T0888 Remote System Information Discovery Remote System Information Discovery targets this object.
Relationship explorer

All related ATT&CK context

targets · Technique T0872: Indicator Removal on Host ICS targets · Technique T0871: Execution through API ICS targets · Technique T1695.002: Ethernet ICS targets · Technique T0822: External Remote Services ICS targets · Technique T0814: Denial of Service ICS targets · Technique T0809: Data Destruction ICS targets · Technique T0820: Exploitation for Evasion ICS targets · Technique T0842: Network Sniffing ICS targets · Technique T0893: Data from Local System ICS targets · Technique T0883: Internet Accessible Device ICS targets · Technique T0823: Graphical User Interface ICS targets · Technique T0830: Adversary-in-the-Middle ICS targets · Technique T0881: Service Stop ICS targets · Technique T1693.001: System Firmware ICS targets · Technique T1695.003: Wi-Fi ICS targets · Technique T0840: Network Connection Enumeration ICS targets · Technique T0892: Change Credential ICS targets · Technique T0846.003: Multicast Discovery ICS targets · Technique T0859: Valid Accounts ICS targets · Technique T0853: Scripting ICS targets · Technique T0890: Exploitation for Privilege Escalation ICS targets · Technique T0866: Exploitation of Remote Services ICS targets · Technique T0862: Supply Chain Compromise ICS targets · Technique T0846.002: Broadcast Discovery ICS
Change history

Object version and sync metadata

The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates .

ATT&CK release
19.1
Object version
1.1
Created
Modified
Raw hash
2f9e18f0e1ed9396...
Imported snapshots across ATT&CK releases (1)
Release Bundle imported Object version Modified Status Raw hash
19.1 1.1 Current bundle 2f9e18f0e1ed…
Raw source

Mirrored ATT&CK source object

The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.

Open mirrored raw JSON Open MITRE-hosted copy
Source references

External references and citations

MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.

  1. [1]
    mitre-attack A0016
    Open source URL
Source and licensing

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