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November 20, 2025

ゼロトラストコントロールとAI駆動の検知でOTリモートアクセスを管理

本稿では、現代のOTが可視性だけに頼ることはできない理由、そしてゼロトラストアクセスコントロールとAI駆動のビヘイビア検知と組み合わせることにより、リアルタイムの監視、アカウンタビリティ、安全なリモートアクセスを、オペレーションを混乱させることなく実現する方法について、今後の展望も見据えて解説します。
Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Pallavi Singh
Product Marketing Manager, OT Security & Compliance
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20
Nov 2025

IT-OT統合へのシフト

近年、産業環境は相互接続が進み外部との連携により依存するようになりました。その結果、真にエアギャップされたOTシステムの現実味は薄れています。特に、OEMが管理するアセットを使用している、レガシー装置に対してリモート診断が必要となる、あるいは第三者のインテグレーターが頻繁に接続するケースなどでは難しいでしょう。

こうした連携は、デジタル変革戦略に基づくもの、あるいは運用効率目標のため、いずれの場合においてもOT環境をより接続された、より自動化された、よりITシステムと絡み合ったものにしつつあります。このような統合により新たな可能性が開かれますが、同時にOT環境は、従来のOTアーキテクチャが耐えるように設計されていないような、さまざまなリスクにさらされることになります。

最新化により生まれるギャップと可視性だけでは不十分な理由

最新化への取り組みにより新たなテクノロジーが産業環境にも導入され、IT環境とOT環境の統合とともに、可視性の欠如も生まれました。しかし、可視性を取り戻すことはスタート地点にすぎません。可視性は何が接続されているかを教えてくれるだけで、アクセスをどのように管理すべきかを教えてはくれません。そしてここがITとOTの分断が避けられなくなるポイントです。

ITではうまく機能するセキュリティ戦略もOTではしばしば不十分なことがあります。OT環境ではわずかな失敗が環境への危険性、安全に関する事故、あるいは多大なコストを伴う稼働の停止などにつながるからです。さらに、安全なアクセス、分割の徹底、説明責任などを求める法規制の高まりからの圧力が加わると、可視性だけではもはや不十分であるということが明確になります。産業環境に今必要なのは、精密性です。そこではコントロールが必要です。そして、オペレーションを中断させることなくその両方を実現する必要があります。それには、アイデンティティベースのアクセス制御、リアルタイムのセッション監視、そして継続的なビヘイビア検知が必要となります。

監視されていないリモートアクセスによるリスク

このリスクは、アセットの故障をトラブルシューティングするためにOEMが緊急にアクセスを必要とする場合など、重大なタイミングで現れます。

限られた時間というプレッシャーのなかで、アクセス権限はしばしば最小限の検証ですばやく付与され、決められたプロセスが省略されることがあります。一旦中に入れば、コマンドの実行、設定の変更、あるいはネットワーク内で水平移動するなど、ユーザーのアクションに対するリアルタイムの監視はないケースがほとんどです。こうしたアクションは多くの場合記録されず、あるいは何かが壊れるまで気づかれません。問題が起こると、チームは断片的なログをつなぎ合わせる作業やインシデント後のフォレンジック作業に追われますが、説明責任の経路は明確ではありません。

アップタイムが決定的に重要であり安全性が譲れない環境においてこのレベルの不透明性では、まったく持続可能ではありません。

可視性のギャップ:誰が何を、いつ行っているか?

私たちが直面している根本的な問題は、誰がアクセス権を持っているかということと、そのアクセス権で何が行われているかという現実がつながっていないことです。  

従来のアクセス管理ツールは認証情報を検証し、入り口を制限するかもしれませんが、セッション中のアクティビティについてリアルタイムの可視性を提供することは稀です。さらに、期待される振る舞いと、侵害、誤使用、設定間違いのかすかな兆候の違いを見分けられるものはさらに少ないでしょう。  

その結果、OTチームとセキュリティチームはしばしば、問題の最も重要なカギとなる、意図と動作が見えない状況に置かれます。

ゼロトラストコントロールとAI駆動の検知でギャップを解消

OTでのリモートアクセスを管理することは、接続権限を付与するだけの問題ではもはやありません。厳密なアクセスパラメーターを徹底すると同時に、異常な振る舞いを継続的に監視することが必要です。これには、精密なアクセスコントロールと、インテリジェントかつリアルタイムの検知という2つの側面からのアプローチが必要です。

ゼロトラストアクセスコントロールが基盤となります。アイデンティティベースの、ジャストインタイム型のアクセス権を適用することにより、OT環境において、外部ベンダーやリモートユーザーが明示的に操作を承認されたシステムに対してのみ、そして必要な時間のみアクセスできるよう徹底できます。これらのコントロールのは、特定のデバイス、コマンド、あるいは機能へのアクセスに制限できるだけの細かさが必要です。これらの原則をPurdueモデル全体に一貫して適用することにより、OT環境を過剰なリスクにさらしてしまうキャッチオール式のVPNトンネル、ジャンプサーバー、そして脆いファイアウォール例外などへの依存を解消することができます。

アクセスコントロールは方程式の1部にすぎない

Darktrace / OT は継続的なAI駆動のビヘイビア検知でゼロトラストコントロールを補強します。静的なルールや事前定義済みのシグネチャに依存する代わりに、Darktraceは自己学習型AIを使用して、あらゆるデバイス、プロトコル、ユーザーに渡る環境全体で何が"正常”かについての、リアルタイムの、変化し続ける理解を構築します。これにより、微細な設定ミス、認証情報の間違った使用、あるいは水平移動を、後から知るのではなく発生と同時にリアルタイムに検知することができます。

ユーザーのアイデンティティとセッション内のアクティビティを、ビヘイビア分析と相関付けることによりDarktraceは全体像を明らかにし、誰がどのシステムにアクセスしたか、どのようなアクションを実行したか、それらのアクションはこれまでの通常状態と比較してどうか、そして逸脱が発生したかどうかを知ることができます。リモートアクセスセッションに関連する当て推量を取り除き、明確な、コンテキストを含めた情報を提供します。

重要な点は、Darktraceがオペレーション内のノイズと本物のサイバー脅威に関連した異常を区別することです。CVEアラートから日常的なアクティビティまですべてを1つのストリームにまとめてしまう他のツールとは異なり、Darktraceは正しいリモートアクセス動作とミスや乱用の可能性を区別します。つまり、組織はコンプライアンスの観点からアクセスを監査できるとともに、セッションがもしエクスプロイトされていれば、その不正な使用は、高確度なサイバー脅威に関連したアラートとして確認できることを意味します。このアプローチはコントロールを補完するものとして利用することができ、もしアクセス権が過剰に拡大されている、あるいは間違って利用されている場合にも、その挙動を可視化し、それに対するアクションが可能です。

たとえば、セッションにおいて、普段とは異なるコマンドシーケンス、新たな水平移動経路、あるいはスケジュールされた時間帯以外のアクティビティが発生するなど、学習したベースラインを逸脱した場合、Darktraceは即座にフラグを立てることができます。これらの情報を基に、人手による調査を開始する、あるいはアクセス権のはく奪やセッション隔離などポリシーに応じて自動的にアクションをトリガーするなどが可能です。

この多層的なアプローチにより、リアルタイムの意思決定が可能になり、中断のないオペレーションが確保され、重要な作業を遅らせたりワークフローを中断したりすることなくあらゆるリモートアクティビティに対して完全な説明責任を担保することができます。

ゼロトラストアクセスとAI駆動の監視の組み合わせ:

  • きめ細かいアクセス適用: ゼロトラスト原則に従いコンプライアンスの要件を満たす、ロールベースの、ジャストインタイムのアクセス。 
  • コンテキストを加えた脅威検知: 自己学習型AIが異常なOT動作をリアルタイムに検知し、脅威をアクセスイベントとユーザーアクティビティに結びつける。 
  • 自動化されたセッション管理: 動作の異常によってアラートや自動制御をトリガーすることができ、アップタイムを維持しつつ封じ込めまでの時間を短縮。
  • Purdueレイヤー全体に渡る完全な可視性: 相関付けされたデータにより、IT、OTレイヤー全体にわたりリモートアクセスイベントをデバイスレベルの動作と結びつけることが可能。
  • スケーラブルかつ受動的な監視: 動作を受動的に学習することによりレガシーシステムやエアギャップされた環境全体をカバーすることが可能、シグネチャやエージェント、侵入型スキャンは必要なし。

妥協のない完全なセキュリティ

オペレーションの敏捷性かそれともセキュリティコントロールか、あるいは可視性かそれとも簡潔性か、これらのどちらかを選ぶ必要はもうありません。ゼロトラストアプローチをリアルタイムのAI検知で強化することにより、権限と動作の両方を認識し、産業オペレーションの現実に即した、多様な環境にスケール可能な、安全なリモートアクセスを実現することができます。

重要インフラの保護において、検知を伴わないアクセスはリスクであり、アクセスコントロールを伴わない検知は不完全だからです。

Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Pallavi Singh
Product Marketing Manager, OT Security & Compliance

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May 21, 2026

Darktrace named a Leader in the 2026 Gartner® Magic Quadrant™ for Network Detection and Response (NDR) For the Second Consecutive Year

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Continued recognition in NDR  

Darktrace has been recognized as a Leader in the 2026 Gartner® Magic Quadrant™ for Network Detection and Response (NDR), marking the second consecutive year in the Leaders quadrant.

We believe this consistency reflects sustained ability to execute, adapt, and deliver outcomes as the market evolves.

While we are immensely proud to be recognized by industry analysts as a Leader in NDR, that's just part of the story. Darktrace was also Named the Only 2025 Gartner® Peer Insights™ Customers’ Choice for Network Detection and Response based on direct customer feedback and real-world experience.

We believe the combination of these two signals is important. One reflects how the market is evaluated. The other reflects how technology performs in practice.

Why Darktrace continues to be recognized as a leader

We believe our position as a Leader for the second consecutive year reflects a combination of our sustained ability to execute in NDR, continued AI innovation, and proven delivery of security outcomes for customers and partners worldwide.

We also feel that our leadership in the NDR market is a testament to our unique and multi-layered AI approach, for which we were recognized as No.7 on Fast Company’s Most Innovative AI Companies of 2026 list, plus one of the hottest AI cybersecurity companies in CRN's AI 100.

Adapting to complex, real-world environments

Organizations are no longer protecting a single network perimeter. They are securing a mix of users, devices, applications, and data that move across hybrid environments.

Darktrace has focused on maintaining visibility and detection across these conditions, allowing security teams to understand activity as it scales.

Supporting organizations globally, not just technically

Security outcomes are shaped as much by deployment and support as they are by detection capability.

Darktrace continues to invest in regional presence across 29 countries around the world, helping organizations operationalize NDR in ways that align with local requirements, internal processes, and team structures.

Continuing to push AI beyond detection

AI in cybersecurity is often positioned as a way to improve detection accuracy. But the more important shift is how AI can influence decision-making and response.

Darktrace continues to develop models that learn from both live environments and historical incident data, combining real-time behavioral analysis with insights derived from prior attack patterns.

Using technologies such as the Incident Graph and DIGEST (Darktrace Incident Graph Evaluation for Security Threats), activity is not analyzed in isolation. Instead, relationships between users, devices, connections, and events are mapped over time, allowing the system to reconstruct how an incident is unfolding and how similar incidents have progressed in the past.

By evaluating these patterns, Darktrace can assess the likelihood that an incident will escalate, prioritizing the activity that poses the greatest risk and surfacing the most relevant context for investigation.

This shifts security operations from simply identifying anomalies to understanding their trajectory, helping teams anticipate potential impact and respond earlier with greater precision.

Why NDR is shifting from reactive detection to proactive, AI-driven security

Traditional approaches to NDR have been built around reactively identifying threats once they become clearly visible. That model is increasingly difficult to rely on.

Attackers are no longer operating in ways that stand out. They use valid credentials, trusted tools, and low-and-slow techniques that blend into everyday activity. By the time something looks obviously malicious, the impact is often already underway.

This is the core limitation of reactive detection. It depends on recognizing something that already looks like a threat.

As a result, many of the most consequential incidents today fall into a gap.

Insider activity, compromised credentials, and novel attacks rarely trigger traditional alerts because they do not follow known patterns. On the surface, they often appear legitimate, making them difficult to distinguish from normal behavior without deeper context.

This is why we believe this Gartner recognition reflects a broader shift in NDR toward autonomous, proactive and pre‑emptive security operations.

By understanding normal behavior within an environment, it is possible to identify subtle deviations rather than waiting for confirmation of threats as they are taking place.

Darktrace’s Self-Learning AI is designed for behavioral understanding. By continuously learning each organization’s normal patterns, it can detect deviations in real time, enabling a proactive and pre-emptive model of NDR where security teams can respond to early signs of risk as they emerge, reducing the window in which attacks can develop.

In multiple cases, this behavioral approach has led to early threat detection where Darktrace identified completely unknown threats, including pre-CVE zero-day activity. By detecting subtle behavioral changes before vulnerabilities were publicly disclosed or widely understood, organizations can mitigate threats before they do damage.

This shift is subtle but important. Modern NDR solutions must shift from a system that explains what happened to one that helps prevent threats from developing in the first place, and Darktrace is proud to be at the forefront of this shift - helping organizations build and maintain a state of proactive network resilience.

Continuing to innovate at the forefront of NDR

In our view, recognition as a Leader reflects where the market is today. Continuing to innovate defines what comes next.

As businesses evolve, new technologies like AI tools and agents introduce new security risks and challenges; security teams need more than simple detection. They need a complete understanding of risk as it develops, the ability to investigate it in context, and to contain threats at machine speed.  

Darktrace / NETWORK is built to deliver across that full spectrum. Its Self-Learning AI continuously adapts to each organization’s environment, identifying subtle behavioral changes that signal emerging threats. Integrated investigation and autonomous response reduce the time between detection and action, allowing teams to move with greater speed and confidence.

This combination enables organizations to detect and contain known, unknown, and insider threats as they develop, while also strengthening resilience over time.

As a two-time Leader in the Gartner® Magic Quadrant™ for NDR and the only 2025 Gartner® Peer Insights™ Customers’ Choice, we feel Darktrace continues to evolve its platform to meet the demands of modern environments, delivering a more complete and adaptive approach to network security.

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Disclaimer: The 2026 Gartner® Magic Quadrant™ for Network Detection and Response (NDR) ,The 2026 Gartner® Magic Quadrant™ for Network Detection and Response (NDR), Thomas Lintemuth, Charanpal Bhogal, Nahim Fazal, 18 May 2026.

Gartner does not endorse any vendor, product or service depicted in its research publications, and does not advise technology users to select only those vendors with the highest ratings or other designation. Gartner research publications consist of the opinions of Gartner’s research organization and should not be construed as statements of fact. Gartner disclaims all warranties, expressed or implied, with respect to this research, including any warranties of merchantability or fitness for a particular purpose.

GARTNER is a registered trademark and service mark of Gartner, Inc. and/or its affiliates in the U.S. and internationally and is used herein with permission. All rights reserved. Magic Quadrant is a registered trademark of Gartner, Inc. and/or its affiliates and is used herein with permission. All rights reserved.

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About the author
Mikey Anderson
Product Marketing Manager, Network Detection & Response

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May 21, 2026

Prompt Security in Enterprise AI: Strengths, Weaknesses, and Common Approaches

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How enterprise AI Agents are changing the risk landscape  

Generative AI Agents are changing the way work gets done inside enterprises, and subsequently how security risks may emerge. Organizations have quickly realized that providing these agents with wider access to tooling, internal information, and granting permissions for the agent to perform autonomous actions can greatly increase the efficiency of employee workflows.

Early deployments of Generative AI systems led many organizations to scope individual components as self-contained applications: a chat interface, a model, and a prompt, with guardrails placed at the boundary. Research from Gartner has shown that while the volume and scope of Agentic AI deployments in enterprise environments is rapidly accelerating, many of the mechanisms required to manage risk, trust, and cost are still maturing.

The issue now resides on whether an agent can be influenced, misdirected, or manipulated in ways that leads to unsafe behavior across a broader system.

Why prompt security matters in enterprise AI

Prompt security matters in enterprise AI because prompts are the primary way users and systems interact with Agentic AI models, making them one of the earliest and most visible indicators of how these systems are being used and where risk may emerge.

For security teams, prompt monitoring is a logical starting point for understanding enterprise AI usage, providing insight into what types of questions are being asked and tasks are being given to AI Agents, how these systems are being guided, and whether interactions align with expected behavior. Complete prompt security takes this one step further, filtering out or blocking sensitive or dangerous content to prevent risks like prompt injection and data leakage.

However, visibility only at the prompt layer can create a false sense of security. Prompts show what was asked, but not always why it was asked, or what downstream actions were triggered by the agent across connected systems, data sources, or applications.

What prompt security reveals  

The primary function of prompt security is to minimize risks associated with generative and agentic AI use, but monitoring and analysis of prompts can also grant insight into use cases for particular agents and model. With comprehensive prompt security, security teams should be able to answer the following questions for each prompt:

  • What task was the user attempting to complete?
  • What data was included in the request, and was any of the data high-risk or confidential?
  • Was the interaction high-risk, potentially malicious, or in violation of company policy?
  • Was the prompt anomalous (in comparison to previous prompts sent to the agent / model)?

Improving visibility at this layer is a necessary first step, allowing organizations to establish a baseline for how AI systems are being used and where potential risks may exist.  

Prompt security alone does not provide a complete view of risk. Further data is needed to understand how the prompt is interpreted, how context is applied, what autonomous actions the agent takes (if any), or what downstream systems are affected. Understanding the outcome of a query is just as important for complete prompt security as understanding the input prompt itself – for example, a perfectly normal, low-risk prompt may inadvertently result in an agent taking a high-risk action.

Comprehensive AI security systems like Darktrace / SECURE AI can monitor and analyze both the prompt submitted to a Generative AI system, as well as the responses and chain-of-thought of the system, providing greater insight into the behavior of the system. Darktrace / SECURE AI builds on the core Darktrace methodology, learning the expected behaviors of your organization and identifying deviations from the expected pattern of life.

How organizations address prompt security today

As prompt-level visibility has become a focus, a range of approaches have emerged to make this activity more observable and controllable. Various monitoring and logging tools aim to capture prompt inputs to be analyzed after the fact.  

Input validation and filtering systems attempt to intervene earlier, inspecting prompts before they reach the model. These controls look for known jailbreak patterns, language indicative of adversarial attacks, or ambiguous instructions which could push the system off course.

Importantly, for a prompt security solution to be accurate and effective, prompts must be continually observed and governed, rather than treated as a point-in-time snapshot.  

Where prompt security breaks down in real environments

In more complex environments, especially those involving multiple agents or extensive tool use, AI security becomes harder to define and control.

Agent-to-Agent communications can be harder to monitor and trace as these happen without direct user interaction. Communication between agents can create routes for potential context leakage between agents, unintentional privilege escalation, or even data leakage from a higher privileged agent to a lower privileged one.

Risk is shaped not just by what is asked, but by the conditions in which that prompt operates and the actions an agent takes. Controls at the orchestration layer are starting to reflect this reality. Techniques such as context isolation, scoped memory, and role-based boundaries aim to limit how far a prompt’s influence can extend.  

Furthermore, Shadow AI usage can be difficult to monitor. AI systems that are deployed outside of formal governance structures and Generative AI systems hosted on unknown endpoints can fly under the radar and can go unseen by monitoring tools, leaving a critical opening where adversarial prompts may go undetected. Darktrace / SECURE AI features comprehensive detection of Shadow AI usage, helping organizations identify potential risk areas.

How prompt security fits in a broader AI risk model

Prompt security is an important starting point, but it is not a complete security strategy. As AI systems become more integrated into enterprise environments, the risks extend to what resources the system can access, how it interprets context, and what actions it is allowed to take across connected tools and workflows.

This creates a gap between visibility and control. Prompt security alone allows security teams to observe prompt activity but falls short of creating a clear understanding of how that activity translates into real-world impact across the organization.

Closing that gap requires a broader approach, one that connects signals across human and AI agent identities, SaaS, cloud, and endpoint environments. It means understanding not just how an AI system is being used, but how that usage interacts with the rest of the digital estate.

Prompt security, in that sense, is less of a standalone solution and more of an entry point into a larger problem: securing AI across the enterprise as a whole.

Explore how Darktrace / SECURE AI brings prompt security to enterprises

Darktrace brings more than a decade of AI expertise, built on an enterprise‑wide platform designed to operate in and understand the behaviors of the complex, ambiguous environments where today’s AI now lives. With Darktrace / SECURE AI, enterprises can safely adopt, manage, monitor, and build AI within their business.  

Learn about Darktrace / SECURE AI here.

Sign up today to stay informed about innovations across securing AI.

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About the author
Jamie Bali
Technical Author (AI) Developer
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