TA0108: Initial Access
The adversary is trying to get into your ICS environment.
Initial Access consists of techniques that adversaries may use as entry vectors to gain an initial foothold within an ICS environment. These techniques include compromising operational technology assets, IT resources in the OT network, and external remote services and websites. They may also target third party entities and users with privileged access. In particular, these initial access footholds may include devices and communication mechanisms with access to and privileges in both the IT and OT environments. IT resources in the OT environment are also potentially vulnerable to the same attacks as enterprise IT systems. Trusted third parties of concern may include vendors, maintenance personnel, engineers, external integrators, and other outside entities involved in expected ICS operations. Vendor maintained assets may include physical devices, software, and operational equipment. Initial access techniques may also leverage outside devices, such as radios, controllers, or removable media, to remotely interfere with and possibly infect OT operations.
Analyst context for executives and security teams
Initial Access for ICS is the business-critical question of how an adversary first gets into an operational technology environment. The ATT&CK description highlights entry through OT assets, IT resources inside OT networks, external remote services and websites, privileged third parties, vendor-maintained assets, and outside devices such as removable media or radios/controllers. For leaders, this matters because the first foothold may sit at the boundary between corporate IT, vendors, and operations—exactly where ownership, monitoring, and response responsibilities are often unclear.
Executive priority
Treat this tactic as a resilience and governance priority, not only a SOC detection issue. Executives should ask who has privileged access into ICS, which IT resources exist inside OT networks, how vendor-maintained assets are governed, and whether remote services, websites, and removable media paths are controlled and auditable. The decision value is in clarifying accountability before an incident: which teams can see access attempts, who can disable or validate third-party access, and what evidence would support incident response, compliance, and operational continuity decisions.
Technical view
Because MITRE provides no tactic-level detection guidance for this object, SOC, OT security, and IR teams should validate coverage around the entry paths named in the official description. Focus on visibility at IT/OT boundary systems, OT-hosted IT resources, remote access mechanisms, vendor or integrator access, privileged user activity, removable media handling, and externally reachable services or websites connected to expected ICS operations. Detection engineering should map local techniques and controls to these access paths rather than assuming enterprise IT monitoring automatically covers OT environments.
Likely telemetry
- Remote access authentication and session logs for systems with access to ICS or OT networks
- Identity and privileged access records for vendors, maintenance personnel, engineers, integrators, and other third parties
- Network flow, firewall, VPN, and boundary monitoring between IT and OT environments
- Asset inventory and configuration evidence for OT assets, IT resources in OT networks, and vendor-maintained devices or software
- Logs from externally accessible services or websites associated with ICS operations
Detection direction
- Validate whether monitoring covers both OT assets and IT resources located in OT networks; do not rely only on corporate IT telemetry.
- Review how third-party and privileged access is logged, approved, time-bounded, and correlated with maintenance activity.
- Tune detections around remote access and boundary activity to account for legitimate vendor and engineering workflows, while preserving evidence of unusual timing, source, destination, or privilege use.
- Confirm whether removable media and outside device activity can be observed or investigated in the ICS environment.
- Identify blind spots where vendor-maintained assets, physical devices, software, or operational equipment are outside normal logging and incident response processes.
Mitigation priorities
- Prioritize governance of remote access and privileged third-party access into ICS, including ownership, approval, logging, and revocation processes.
- Maintain an accurate inventory of OT assets, IT resources in OT networks, externally reachable services, and vendor-maintained equipment or software.
- Reduce unnecessary IT/OT connectivity and ensure boundary controls are enforceable and monitored.
- Establish operational procedures for removable media and outside devices that may interact with OT operations.
- Prepare incident response playbooks that define how to validate, contain, and communicate suspected initial access without disrupting critical operations unnecessarily.
Analyst notes and limits
This is a tactic-level ICS ATT&CK object, so it describes the adversary objective rather than a specific technique. The strongest defensive use is as a scoping and readiness checklist for ICS entry paths: OT assets, IT resources in OT networks, remote services, websites, privileged third parties, vendor-maintained assets, and outside devices. Local architecture, access patterns, and operational constraints are required to convert this into specific detections or controls.
No official detection text, platforms, tactics list, aliases, labels, or relationship context were supplied. This take does not assert active exploitation, attribution, specific tools, or guaranteed detection coverage. Recommendations are limited to defensive validation directions supported by the official description.
Initial Access
The adversary is trying to get into your ICS environment.
Initial Access consists of techniques that adversaries may use as entry vectors to gain an initial foothold within an ICS environment. These techniques include compromising operational technology assets, IT resources in the OT network, and external remote services and websites. They may also target third party entities and users with privileged access. In particular, these initial access footholds may include devices and communication mechanisms with access to and privileges in both the IT and OT environments. IT resources in the OT environment are also potentially vulnerable to the same attacks as enterprise IT systems. Trusted third parties of concern may include vendors, maintenance personnel, engineers, external integrators, and other outside entities involved in expected ICS operations. Vendor maintained assets may include physical devices, software, and operational equipment. Initial access techniques may also leverage outside devices, such as radios, controllers, or removable media, to remotely interfere with and possibly infect OT operations.
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.
All related ATT&CK context
No relationships are available in the current normalized data for this object.
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 .
Imported snapshots across ATT&CK releases (1)
| Release | Bundle imported | Object version | Modified | Status | Raw hash |
|---|---|---|---|---|---|
| 19.1 | 1.0 | Current bundle | eb6fb82c5300… |
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.
External references and citations
MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.
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mitre-attack TA0108Open source URL
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