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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
Senior Product Marketing Manager
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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
Senior Product Marketing Manager

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August 26, 2026

AI Agents: Securing the Path from Intent to Action

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The UK’s National Cyber Security Centre (NCSC) recently published guidance on managing the cyber risk of agentic AI. While the document is framed as interim advice as more formal guidance is developed, the framing reflects the current state of the industry: organizations are already deploying agents into production environments while standards, controls, and operating models for autonomous systems remain unsettled. Governance is evolving alongside adoption rather than preceding it, a reality which underscores the importance of robust controls.  

The NCSC’s guidance recommends aligning controls to an agent's level of autonomy, assigning distinct identities, limiting permissions, constraining access to systems and data, monitoring activity, maintaining human oversight, and preserving the ability to intervene when necessary. Most of these recommendations will sound familiar to security teams. The challenge is not the novelty of the controls. It is the type of system those controls now need to govern.

The shift from model security to agent security

For several years, AI security discussions have focused heavily on models. Can a model be manipulated? Jailbroken? Trusted? Can it expose information it should not? Those questions remain important, but they capture only part of the problem. A model generating text is one thing. A system connected to identities, applications, tools, workflows, and business data is another.

The difference becomes clearer when comparing a chatbot that answers questions with an agent that can retrieve customer records, update tickets, invoke tools, trigger workflows, and interact with external systems. The underlying model may be identical. Its access is not. The security question begins to shift from what the model knows to what the system can do.

The same theme appears in the Five Eyes statement released earlier this year, describing AI as a force multiplier that is accelerating both offensive and defensive cyber operations. The NCSC guidance explores what that reality looks like when autonomous systems begin operating inside enterprise environments.

Securing AI agents in operation

The NCSC spends relatively little time debating model behavior and considerably more time discussing identity, permissions, monitoring, oversight, containment, and response. Agents are treated as participants within an environment rather than isolated pieces of technology.  

That's broadly consistent with how we think about the problem at Darktrace.

An agent should not be treated as an extension of a user account. It develops its own behavioral patterns. It accesses systems, interacts with data, invokes tools, and moves across workflows in ways that can be observed independently. Understanding what an agent is permitted to do matters. Understanding how it actually behaves once deployed, and whether that behavior aligns with business intent, matters just as much.

Identity provides an obvious example. The NCSC recommends assigning distinct identities to agents rather than allowing them to disappear into surrounding human or service accounts. Most importantly, assigning agents distinct identities enables independent behavioral monitoring.

Development assumptions vs. real-world behavior

The same principle extends to monitoring. NCSC guidance places agent activity within normal security operations rather than treating it as a separate AI governance function. Many of the controls described are put in place before an agent begins operating. Sandboxing, credential design, approval workflows and human oversight all reflect judgments about how the system is expected to behave and what risks it is likely to create.

Actual use may challenge those assumptions. Access patterns change. Workflows expand. Systems begin interacting with resources they have never touched before. Processes that appeared reasonable during design behave differently in production. Human oversight requirements may turn out to be either excessive or inadequate once the system is operating at scale and operating within the context of unique business processes.

The Five Eyes statement points to a similar issue: organizations need confidence that controls continue to work as intended once systems are exposed to real users, data, tools and operational pressures. Often, the question is not whether an agent is technically allowed to perform an action, but whether its behavior remains consistent with the role it was intended to play.

Monitoring and governance of AI agents go hand-in-hand

This problem is exactly why monitoring and governance should be treated as part of the same process. Governance sets the initial parameters for deployment, while monitoring provides evidence about whether those parameters remain appropriate. That evidence should, in turn, inform changes to permissions, controls and oversight.

This matters increasingly as autonomous systems are integrated into business processes. The relevant risk is shaped not only by the model or agent itself, but by what it can access, what actions it can take, and how its behavior changes in practice.

Developing continuous oversight of AI agent behavior

The implication is clear: governance cannot end at deployment. Organizations need a way to understand how agents behave after deployment, test whether controls remain appropriate, and adjust them as conditions change. That requires visibility not just into technical activity, but into whether that activity makes sense in the context of the business process the agent is intended to support.

This is where business-centric behavioral security can become critical. Risk does not emerge from the model itself: it emerges from the actions an autonomous system takes within the enterprise and the downstream consequences of those actions.  

An agent can operate exactly as intended and still create risk if it accesses sensitive information in an unexpected context, exercises permissions in ways that create unintended exposure, or influences business processes in ways that were not anticipated during design and review.

Traditional governance vs. behavioral security

Traditional governance frameworks provide assurance at a point in time. Behavioral security can provide ongoing visibility into how autonomous systems interact with the organization they are meant to serve. Rather than focusing exclusively on model performance or policy compliance, organizations need to understand whether an agent's behavior aligns with business intent, operational expectations, and acceptable risk tolerances as conditions change.

As enterprises move from isolated AI deployments to interconnected ecosystems of agents, visibility into behavior becomes as important as visibility into code. Governance determines what an autonomous system is permitted to do. Behavioral analytics helps determine what it is doing, what business outcomes it is producing, and whether those outcomes remain aligned with the organization's objectives.

[related-resource]

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About the author
Margaret Cunningham, PhD
VP, Security & AI Strategy, Field CISO

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August 26, 2026

When AI Becomes the Lure: A Fake Gemini Installer Delivers Vidar

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Key takeaways

  • Darktrace observed a customer download a fake Google Gemini installer hosted on Google Colab, resulting in the execution of the Vidar information stealer.
  • Darktrace identified the compromise through behavioral indicators, including suspicious process activity, anomalous network communications, and indicators of credential theft, before autonomously containing the threat.
  • The incident highlights how threat actors are increasingly exploiting trusted platforms and a growing interest in AI tools to distribute malware through seemingly legitimate software acquisition workflows.

The Growing Abuse of Generative AI

As organizations are increasingly adopting generative AI tools into their daily workflows, attackers are adapting their distribution methods accordingly too. As part of their day-to-day work, users are now searching for AI assistants, programming tools, browser extensions, desktop applications, and productivity integrations.

Recent reports have highlighted campaigns that use fake AI software and AI-related installers to distribute malware and steal credentials [1]. Researchers have documented campaigns that exploit fake AI-themed websites and services to distribute information stealers and backdoors [2]. Security researchers have also observed attackers disguising malware as legitimate installers for AI software to increase the likelihood of victim interaction and execution [3].

In July 2026, Darktrace observed one such case within a customer environment in the Europe, Middle East and Africa (EMEA) region, where attackers used a fake generative AI installer to deliver the prolific information stealer Vidar. This incident highlights how threat actors are exploiting interest in AI services to distribute established malware using increasingly convincing social engineering techniques.

How a Fake Gemini Installer Delivered Vidar

Initial Access: From Search Result to Malware Download

Unlike many malware campaigns that begin with a phishing email, this activity appears to have originated from a user searching for and downloading software.

Darktrace first observed unusual activity on the customer network after a suspicious executable file was launched from a user’s Download folder. Further investigation revealed that the file purported to be a Google Gemini installer and was named “Download_Google_Gemini_For_Windows.exe”.

During the initial analysis, it was noted that the top search result for the suspicious filename associated pointed to a file hosted on Google Colab, a cloud-based Jupyter notebook platform, commonly used by developers, researchers, and data scientists to run code and machine learning workloads through a web browser. By leveraging another trusted Google platform, the attacker increased the likelihood that users would perceive the download as legitimate, making the lure more convincing to those searching for Gemini-related software.

Figure 1: The Google Colab page containing a download prompt for the fake Google Gemini installer.

Further investigation of the Google Colab page revealed that the download prompt redirected users to a secondary site, hxxps://micronsoftwares[.]com, which posed as a "Windows Software Hub" download page and offered the fake Gemini installer for download.

Figure 2: The secondary website posing as a "Windows Software Hub" download page, which likely hosted the fake Gemini installer.

While the investigation did not uncover any HTTP or file-download telemetry data that conclusively identified the download source, SSL communication sessions with Google Colab were detected immediately before the suspicious file was executed. The timing of these connections suggests that the user interacted with the Colab resource before being redirected to the secondary site from which the executable was downloaded.

The user was not simply tricked into opening an email attachment; instead, the attacker embedded malicious content into a process many users would consider entirely legitimate: searching for and downloading software associated with a trusted platform.

Weaponizing Trusted Platforms

At the time of review (July 15, 2026), Darktrace's Threat Research team confirmed that the Google Colab page was still active and prompting users to download a ZIP archive containing the binary file.

The archive also appeared to contain a README file instructing users to run the binary file with administrator privileges and add it to their antivirus software’s exception lists. These instructions suggest that the campaign relied heavily on social engineering, convincing users to take actions that would facilitate malware execution and potentially bypass security checks.

The use of a legitimate platform also complicates the user’s decision-making. Downloads associated with a trusted service are often perceived as less suspicious than those hosted on unfamiliar domains. When combined with the branding of a widely used AI tool, the lure becomes even more convincing.

Malware Analysis

Darktrace’s Threat Research team identified the executable file as the information-stealing malware Vidar. Analysis revealed that the binary file was a newer Go-compiled variant that communicated with Telegram-based infrastructure. Darktrace’s researchers also identified dtm[.]kijangturbo88[.]top as a command-and-control (C2) endpoint associated with the activity. While the malware itself was not novel, the lure and delivery mechanism was.

For a deeper look at the information stealer, see Darktrace’s 2023 analysis of Vidar.

Figure 3: Darktrace’s detection of the unusual outbound connection associated with the fake Gemini installer.

Shortly after execution, the process established communications with the external IP address 91.98.98[.]86 via port 443, directly linking the executable to suspicious network activity observed on the device. Subsequent open-source intelligence (OSINT) analysis of the revealed multiple malicious associations [5].

Additional Darktrace detections included unusual SSL activity from the affected device. Analysis of related SSL telemetry identified 91.98.111[.]49 as additional infrastructure associated  with the activity [6].

Subsequent alerts from the customer's Microsoft Defender for Endpoint integration later confirmed activity consistent with the theft of browser credentials and other sensitive data from the affected endpoint.

Taken together, these detections provided a clear picture of the attack, from the execution of a suspicious file and unusual network connections to indicators of C2 activity and credential theft.

Figure 4: Darktrace’s detection of anomalous activity following the execution of the fake Gemini installer, seen in the Model Alert Event Log.

Darktrace's Autonomous Response

Following the detection, Darktrace’s Autonomous Response took immediate containment action, including blocking communication with suspicious external infrastructure, including 91.98.98[.]86, and quarantining the compromised device.

Despite the apparent legitimacy of the activity, with the installer hosted on a trusted platform and resembling a routine software download, Darktrace was able to detect and contain the attack because the device's behavior deviated from its normal pattern.

Figure 5: Automated containment actions implemented by Darktrace's Autonomous Response following the detection of activity associated with the fake Gemini installer.

Conclusion

This investigation highlights how threat actors continue to adapt established malware delivery techniques to emerging technology trends. While the malware itself was not new, the distribution method was. By disguising Vidar as a Google Gemini installer and hosting the malicious content on a trusted platform, the attack aligned its lure with a growing behavioral trend: users actively searching for AI tools and services as part of their day-to-day work.

Although fake installers are not a new phenomenon, the rapid rise of generative AI has created new opportunities for threat actors. Rather than relying solely on traditional delivery methods, attackers can now target users who are actively searching for AI applications. As AI adoption continues to accelerate across enterprise environments, organizations should remain alert to campaigns that exploit this interest through fake applications, malicious websites, manipulated search results, the misuse of trusted platforms, and AI-themed social engineering.

Credit to Rushanth Ramanathan (Cyber Analyst) Joanna Ng (Detection Engineer)

Edited by Ryan Traill (Content Manager)

Appendices

Darktrace Model Detections

  • Security Integration / C2 Activity and Integration Detection
  • Endpoint / New Suspicious Executable Launched
  • Endpoint / Process Connection / Unusual Connection from New Process
  • Anomalous Connection / Rare External SSL Self-Signed
  • Security Integration / High Severity Integration Detection
  • Antigena / Network / Significant Anomaly /  Antigena Significant Security Integration and Network Activity Block

•Antigena / Network / Significant Anomaly /  Antigena Significant Anomaly from Client Block

List of Indicators of Compromise (IoCs)

IoC Type Description
Download_Google_Gemini_For_Windows.exe File Fake Gemini-themed installer observed during the investigation.
GoogleAppInstaller.exe File Related executable identified through endpoint telemetry.
91.98.98[.]86 IP Address External destination contacted by the malicious executable.
91.98.111[.]49 IP Address Related infrastructure identified through SSL certificate pivoting.
dtm[.]kijangturbo88[.]top Domain Command-and-control endpoint identified during malware analysis.
1e13c2c9eac72daf63fd00a9946878949e159ae6ec51b54ec64f942d79d61913 SHA256 Malware sample associated with the fake Gemini installer.

MITRE ATT@CK Mapping


MITRE ATT&CK Mapping Tactic Technique
Initial Access T1204 User Execution
Execution T1204.002 User Execution: Malicious File
Defence Evasion T1036 Masquerading
Credential Access T1555 Credentials from Password Stores
Credential Access T1555.003 Credentials from Web Browsers
Command and Control T1071 Application Layer Protocol
Exfiltration T1041 Exfiltration Over C2 Channel
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About the author
Rushanth Ramanathan
Cyber Analyst
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