Blog
July 31, 2025

The Microsoft Copilot Data Exposure Playbook: New Incidents Need New Responses

Traditional incident response approaches fail with Microsoft Copilot because they're designed for external attacks, not internal AI systems that synthesise and correlate organisational data across Microsoft 365, requiring new forensic approaches, different containment strategies, and specialised team skills to handle incidents that are largely preventable through proper data governance before deployment.

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TL;DR: Traditional incident response approaches fail when Microsoft Copilot causes data breaches because they're designed for external attacks, not internal AI systems that synthesise and correlate organisational data inappropriately across Microsoft 365. Copilot incidents require new forensic approaches, different containment strategies, and specialised team skills. Most Copilot incidents are preventable through proper data governance before deployment, but when they occur, organisations need frameworks that treat Copilot incidents as a unique discipline requiring dedicated tools and trained personnel.

Your incident response team just got called about a "data exposure incident involving Microsoft Copilot." The challenge? Everything they know about containing breaches doesn't apply here.

Why traditional incident response approaches fail with Microsoft Copilot

Traditional incident response assumes you can isolate compromised systems, revoke access, and contain the damage. With Microsoft Copilot, the damage is already done the moment it synthesises and shares information across your Microsoft 365 environment. You can't "un-correlate" data that's been combined from SharePoint, Teams, Outlook, and OneDrive in a single Copilot response.

What this looks like: An HR manager asks Microsoft Copilot to "analyse employee engagement across departments" and receives detailed salary information, performance reviews, and disciplinary records pulled from Excel files, SharePoint sites, and Teams conversations that were technically accessible but never actively viewed. By the time security discovers the issue three weeks later, the Copilot-generated summary has been shared with five other managers through Teams and referenced in three PowerPoint presentations.

The forensic challenge is significant. Unlike traditional breaches where attackers leave obvious traces, Microsoft Copilot incidents often look like normal Microsoft 365 operations. This challenge is compounded by the fact that 86% of business leaders with cybersecurity responsibilities reported at least one AI-related incident in the past 12 months (2025 Cisco Cybersecurity Readiness Index), yet only 49% of respondents believe employees fully understand AI-related cybersecurity threats (2025 Cisco Cybersecurity Readiness Index). An employee asking Copilot to "analyse our competitive position" and receiving confidential financial data appears as legitimate usage in Microsoft Purview audit logs.

How do you investigate a Microsoft Copilot data correlation incident?

Traditional forensic tools can't reconstruct how Microsoft Copilot accessed, processed, and synthesised information across your entire Microsoft 365 environment. When someone asks Copilot to "summarise our Q3 performance," it might correlate financial reports from SharePoint, customer complaints from Teams, operational metrics from Excel files, and strategic planning documents from OneDrive – creating a comprehensive analysis that no human would have consciously assembled.

What this looks like: Your forensic team can tell you exactly which Microsoft 365 files were accessed and when through audit logs, but they can't easily determine what sensitive insights Copilot generated by combining quarterly sales data from Excel with customer satisfaction surveys from Forms and internal strategy documents from SharePoint. Traditional digital forensics assumes you can examine compromised systems in isolation. Microsoft Copilot incidents require understanding not just what Microsoft 365 data was accessed, but how Copilot correlated and synthesised it across the organisation's environment.

The EchoLeak vulnerability (CVE-2025-32711), discovered by researchers at Aim Security, demonstrated how attackers could trigger data extraction from Microsoft 365 Copilot simply by sending an email with no user interaction required. Microsoft patched this specific vulnerability, but it demonstrates how Copilot creates entirely new attack surfaces within Microsoft 365 that traditional security monitoring cannot detect.

What should your first 60 minutes look like when a Microsoft Copilot incident hits?

Your incident response team needs to determine scope before Microsoft 365 audit logs start overwriting and Copilot-generated content gets buried in normal business communications across Teams, Outlook, and SharePoint. They need to identify which Copilot interactions are involved, what Microsoft 365 data sources Copilot accessed, and how many users potentially received inappropriate Copilot-generated content.

Critical first-hour actions for Microsoft Copilot incidents:

  • Preserve Microsoft Copilot interaction logs before they expire (Copilot audit logs retain for 180 days by default)
  • Document all Copilot-generated outputs – screenshots from Teams, chat exports from Copilot, email summaries
  • Identify affected user sessions across all Microsoft 365 services where Copilot operates
  • Determine which Microsoft 365 data sources Copilot accessed during the timeframe in question using audit logs

What this looks like: Your security team discovers that a senior executive's Microsoft Copilot session combined customer acquisition data from Dynamics with competitive intelligence reports from SharePoint and financial projections from Excel. Traditional incident response would focus on which Microsoft 365 systems were compromised. Copilot incident response must focus on what new sensitive information was created through Microsoft 365 data correlation and who received it through Teams, email, or shared documents.

Why Microsoft Copilot incidents create amplification effects across Microsoft 365

Microsoft Copilot incidents create amplification effects that traditional risk assessment models cannot capture. A single Copilot query can synthesise information from hundreds of Microsoft 365 documents, creating new sensitive data combinations that exceed the classification level of any individual SharePoint file, Teams message, or Outlook email.

The scope of AI-related incidents reflects this amplification: 43% of organisations experienced model theft or unauthorized access, 42% faced AI-enhanced social engineering attacks, and 38% dealt with data poisoning attempts in the past year.

What this looks like: A marketing manager asks Microsoft Copilot for "customer feedback analysis" and receives a summary combining customer complaints from Teams with internal pricing strategy documents from SharePoint and competitive intelligence reports from OneDrive. The Copilot-generated analysis reveals confidential pricing models and strategic plans that no human would have consciously connected across these Microsoft 365 services. By the time the incident is discovered, the summary has been shared with external consultants through Teams and referenced in a PowerPoint presentation.

This is the Microsoft Copilot amplification problem. The marketing manager had legitimate access to customer feedback data in Teams and general market research in SharePoint. But Copilot's synthesis across Microsoft 365 created a strategic intelligence document that combined information across security boundaries, revealing insights that were more sensitive than any individual Microsoft 365 data source.

How is containment different when Microsoft Copilot is your own system?

Traditional containment strategies – cutting network access, revoking credentials, isolating systems – don't work with Microsoft Copilot incidents because the exposure has already occurred through data synthesis across your Microsoft 365 environment and sharing through Teams, email, and collaborative documents.

What this looks like: Your IR team discovers that Microsoft Copilot inappropriately combined customer data from Dynamics with financial projections from Excel in response to an executive's strategic planning question in Teams. They immediately revoke the executive's Copilot license, but the Copilot-generated analysis has already been shared with the leadership team through Teams, saved in multiple SharePoint documents, and referenced in ongoing strategic PowerPoint presentations.

Recovery requires process changes across Microsoft 365, not just technical remediation:

  • Immediate access revocation: Remove Microsoft Copilot licenses for affected users while maintaining Microsoft Purview audit capabilities
  • Data re-classification: Implement emergency reviews for all Microsoft 365 information accessed during the Copilot incident
  • Communication quarantine: Identify and flag all Teams messages, Outlook emails, and SharePoint documents containing Copilot-generated summaries from the incident period

The containment paradox is this: traditional incident response focuses on stopping ongoing damage, but with Microsoft Copilot incidents, the damage occurs in the synthesis moment across Microsoft 365. Once Copilot has correlated sensitive information from SharePoint, Teams, and Outlook and shared it, containment becomes a business process challenge rather than a technical one.

What skills does your incident response team need for the Microsoft Copilot era?

Traditional IR teams focus on malware analysis and network forensics. Microsoft Copilot-ready teams need data scientists who understand Microsoft Graph API, privacy analysts familiar with Microsoft 365 data flows, and Copilot governance specialists.

The skills gap is evident: only 49% of respondents believe employees fully understand AI-related cybersecurity threats, and under half (45%) feel their company has the internal resources and expertise to conduct comprehensive AI security assessments.

What this looks like: Your current IR team can tell you exactly what Microsoft 365 files an attacker accessed and how they moved through your SharePoint environment. But when asked "what sensitive information did Microsoft Copilot create by combining quarterly sales reports from Excel with customer complaint data from Teams?" they face significant challenges. They understand technical indicators of compromise in Microsoft 365 but not the complexities of inappropriate data correlation across Copilot interactions.

Required skills for Microsoft Copilot incident response:

  • Microsoft Copilot literacy: Understanding how Copilot accesses and synthesises data across Microsoft 365 services
  • Data analysis: Ability to assess the sensitivity of Copilot-generated content combinations from multiple Microsoft 365 sources
  • Microsoft 365 investigation: Expertise in Microsoft Graph API and data flows across SharePoint, Teams, OneDrive, and Outlook
  • Business context understanding: Ability to assess when Microsoft Copilot data correlations violate business boundaries

Why are most Microsoft Copilot incidents entirely preventable?

Most Microsoft Copilot incidents are entirely preventable. They're not sophisticated attacks or zero-day exploits – they're the inevitable result of deploying Copilot on top of years of poor Microsoft 365 data governance and permission management across SharePoint, Teams, and OneDrive.

The data supports this reality: while 22% of organisations have unrestricted access to publicly available AI tools, 60% of IT teams report they can't see specific prompts or requests made by employees using GenAI tools. Additionally, 60% of organisations lack confidence in their ability to identify the use of unapproved AI tools in their environments.

What this looks like: Your organisation rushes to deploy Microsoft Copilot because competitors are gaining productivity advantages. IT enables Copilot for the entire organisation without first auditing who has access to what data across SharePoint sites, Teams channels, and OneDrive folders. Three months later, you're dealing with your first Copilot incident when someone in Marketing asks for "competitive analysis" and receives confidential pricing strategies from Excel, M&A discussions from Teams, and customer acquisition costs from SharePoint that were technically accessible through existing permissions but scattered across different Microsoft 365 services.

The preventable reality is that this Microsoft Copilot incident was visible months before it happened. Your SharePoint sprawl, Teams "Everyone" permissions, and legacy OneDrive access controls all pointed to exactly this type of Copilot exposure. But fixing Microsoft 365 data governance feels like infrastructure work while deploying Copilot feels like innovation.

Why this matters: Every successful Microsoft Copilot incident response starts with the same uncomfortable realisation – this incident was entirely predictable and preventable through proper Microsoft 365 permission management. Organisations that proactively secure their Microsoft 365 information architecture before Copilot deployment experience dramatically fewer incidents and much faster recovery times when Copilot incidents do occur.

The uncomfortable truth about Microsoft Copilot incident response

Traditional IR approaches assume you're investigating what an attacker did to your systems. With Microsoft Copilot incidents, you're investigating what your own Microsoft 365 environment did with your data – and that requires an entirely different approach.

The most successful organisations treat Microsoft Copilot incident response as a specialised discipline requiring dedicated tools, trained personnel familiar with Microsoft 365 architecture, and executive support. Those that try to apply traditional IR frameworks to Copilot incidents face longer detection times, higher costs, and incomplete damage assessment across their Microsoft 365 environment.

The reality is clear: organisations will experience Microsoft Copilot-related security incidents. Nearly three quarters (71%) of cybersecurity professionals believe that a cybersecurity incident is likely to disrupt their organisations' business within the next 12 to 24 months (2025 Cisco Cybersecurity Readiness Index). However, only 4% of companies have reached mature readiness levels across all cybersecurity pillars, with 70% remaining in the bottom two categories of preparedness (2025 Cisco Cybersecurity Readiness Index). The question isn't whether your Copilot deployment will cause a data exposure across Microsoft 365 – it's whether your incident response team will be ready to handle it effectively.

Microsoft Copilot incidents don't follow traditional attack patterns because they're not attacks – they're Copilot features working exactly as designed across your Microsoft 365 environment, just with unintended consequences. Your incident response framework needs to account for this fundamental difference in how Copilot operates within Microsoft 365.

Welcome to the Microsoft Copilot incident response era. Your team will need to adapt to these new challenges.

‍

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Ben van Enckevort

CTO and Co-Founder

Ben van Enckevort is the co-founder and CTO of Metomic

TL;DR: Traditional incident response approaches fail when Microsoft Copilot causes data breaches because they're designed for external attacks, not internal AI systems that synthesise and correlate organisational data inappropriately across Microsoft 365. Copilot incidents require new forensic approaches, different containment strategies, and specialised team skills. Most Copilot incidents are preventable through proper data governance before deployment, but when they occur, organisations need frameworks that treat Copilot incidents as a unique discipline requiring dedicated tools and trained personnel.

Your incident response team just got called about a "data exposure incident involving Microsoft Copilot." The challenge? Everything they know about containing breaches doesn't apply here.

Why traditional incident response approaches fail with Microsoft Copilot

Traditional incident response assumes you can isolate compromised systems, revoke access, and contain the damage. With Microsoft Copilot, the damage is already done the moment it synthesises and shares information across your Microsoft 365 environment. You can't "un-correlate" data that's been combined from SharePoint, Teams, Outlook, and OneDrive in a single Copilot response.

What this looks like: An HR manager asks Microsoft Copilot to "analyse employee engagement across departments" and receives detailed salary information, performance reviews, and disciplinary records pulled from Excel files, SharePoint sites, and Teams conversations that were technically accessible but never actively viewed. By the time security discovers the issue three weeks later, the Copilot-generated summary has been shared with five other managers through Teams and referenced in three PowerPoint presentations.

The forensic challenge is significant. Unlike traditional breaches where attackers leave obvious traces, Microsoft Copilot incidents often look like normal Microsoft 365 operations. This challenge is compounded by the fact that 86% of business leaders with cybersecurity responsibilities reported at least one AI-related incident in the past 12 months (2025 Cisco Cybersecurity Readiness Index), yet only 49% of respondents believe employees fully understand AI-related cybersecurity threats (2025 Cisco Cybersecurity Readiness Index). An employee asking Copilot to "analyse our competitive position" and receiving confidential financial data appears as legitimate usage in Microsoft Purview audit logs.

How do you investigate a Microsoft Copilot data correlation incident?

Traditional forensic tools can't reconstruct how Microsoft Copilot accessed, processed, and synthesised information across your entire Microsoft 365 environment. When someone asks Copilot to "summarise our Q3 performance," it might correlate financial reports from SharePoint, customer complaints from Teams, operational metrics from Excel files, and strategic planning documents from OneDrive – creating a comprehensive analysis that no human would have consciously assembled.

What this looks like: Your forensic team can tell you exactly which Microsoft 365 files were accessed and when through audit logs, but they can't easily determine what sensitive insights Copilot generated by combining quarterly sales data from Excel with customer satisfaction surveys from Forms and internal strategy documents from SharePoint. Traditional digital forensics assumes you can examine compromised systems in isolation. Microsoft Copilot incidents require understanding not just what Microsoft 365 data was accessed, but how Copilot correlated and synthesised it across the organisation's environment.

The EchoLeak vulnerability (CVE-2025-32711), discovered by researchers at Aim Security, demonstrated how attackers could trigger data extraction from Microsoft 365 Copilot simply by sending an email with no user interaction required. Microsoft patched this specific vulnerability, but it demonstrates how Copilot creates entirely new attack surfaces within Microsoft 365 that traditional security monitoring cannot detect.

What should your first 60 minutes look like when a Microsoft Copilot incident hits?

Your incident response team needs to determine scope before Microsoft 365 audit logs start overwriting and Copilot-generated content gets buried in normal business communications across Teams, Outlook, and SharePoint. They need to identify which Copilot interactions are involved, what Microsoft 365 data sources Copilot accessed, and how many users potentially received inappropriate Copilot-generated content.

Critical first-hour actions for Microsoft Copilot incidents:

  • Preserve Microsoft Copilot interaction logs before they expire (Copilot audit logs retain for 180 days by default)
  • Document all Copilot-generated outputs – screenshots from Teams, chat exports from Copilot, email summaries
  • Identify affected user sessions across all Microsoft 365 services where Copilot operates
  • Determine which Microsoft 365 data sources Copilot accessed during the timeframe in question using audit logs

What this looks like: Your security team discovers that a senior executive's Microsoft Copilot session combined customer acquisition data from Dynamics with competitive intelligence reports from SharePoint and financial projections from Excel. Traditional incident response would focus on which Microsoft 365 systems were compromised. Copilot incident response must focus on what new sensitive information was created through Microsoft 365 data correlation and who received it through Teams, email, or shared documents.

Why Microsoft Copilot incidents create amplification effects across Microsoft 365

Microsoft Copilot incidents create amplification effects that traditional risk assessment models cannot capture. A single Copilot query can synthesise information from hundreds of Microsoft 365 documents, creating new sensitive data combinations that exceed the classification level of any individual SharePoint file, Teams message, or Outlook email.

The scope of AI-related incidents reflects this amplification: 43% of organisations experienced model theft or unauthorized access, 42% faced AI-enhanced social engineering attacks, and 38% dealt with data poisoning attempts in the past year.

What this looks like: A marketing manager asks Microsoft Copilot for "customer feedback analysis" and receives a summary combining customer complaints from Teams with internal pricing strategy documents from SharePoint and competitive intelligence reports from OneDrive. The Copilot-generated analysis reveals confidential pricing models and strategic plans that no human would have consciously connected across these Microsoft 365 services. By the time the incident is discovered, the summary has been shared with external consultants through Teams and referenced in a PowerPoint presentation.

This is the Microsoft Copilot amplification problem. The marketing manager had legitimate access to customer feedback data in Teams and general market research in SharePoint. But Copilot's synthesis across Microsoft 365 created a strategic intelligence document that combined information across security boundaries, revealing insights that were more sensitive than any individual Microsoft 365 data source.

How is containment different when Microsoft Copilot is your own system?

Traditional containment strategies – cutting network access, revoking credentials, isolating systems – don't work with Microsoft Copilot incidents because the exposure has already occurred through data synthesis across your Microsoft 365 environment and sharing through Teams, email, and collaborative documents.

What this looks like: Your IR team discovers that Microsoft Copilot inappropriately combined customer data from Dynamics with financial projections from Excel in response to an executive's strategic planning question in Teams. They immediately revoke the executive's Copilot license, but the Copilot-generated analysis has already been shared with the leadership team through Teams, saved in multiple SharePoint documents, and referenced in ongoing strategic PowerPoint presentations.

Recovery requires process changes across Microsoft 365, not just technical remediation:

  • Immediate access revocation: Remove Microsoft Copilot licenses for affected users while maintaining Microsoft Purview audit capabilities
  • Data re-classification: Implement emergency reviews for all Microsoft 365 information accessed during the Copilot incident
  • Communication quarantine: Identify and flag all Teams messages, Outlook emails, and SharePoint documents containing Copilot-generated summaries from the incident period

The containment paradox is this: traditional incident response focuses on stopping ongoing damage, but with Microsoft Copilot incidents, the damage occurs in the synthesis moment across Microsoft 365. Once Copilot has correlated sensitive information from SharePoint, Teams, and Outlook and shared it, containment becomes a business process challenge rather than a technical one.

What skills does your incident response team need for the Microsoft Copilot era?

Traditional IR teams focus on malware analysis and network forensics. Microsoft Copilot-ready teams need data scientists who understand Microsoft Graph API, privacy analysts familiar with Microsoft 365 data flows, and Copilot governance specialists.

The skills gap is evident: only 49% of respondents believe employees fully understand AI-related cybersecurity threats, and under half (45%) feel their company has the internal resources and expertise to conduct comprehensive AI security assessments.

What this looks like: Your current IR team can tell you exactly what Microsoft 365 files an attacker accessed and how they moved through your SharePoint environment. But when asked "what sensitive information did Microsoft Copilot create by combining quarterly sales reports from Excel with customer complaint data from Teams?" they face significant challenges. They understand technical indicators of compromise in Microsoft 365 but not the complexities of inappropriate data correlation across Copilot interactions.

Required skills for Microsoft Copilot incident response:

  • Microsoft Copilot literacy: Understanding how Copilot accesses and synthesises data across Microsoft 365 services
  • Data analysis: Ability to assess the sensitivity of Copilot-generated content combinations from multiple Microsoft 365 sources
  • Microsoft 365 investigation: Expertise in Microsoft Graph API and data flows across SharePoint, Teams, OneDrive, and Outlook
  • Business context understanding: Ability to assess when Microsoft Copilot data correlations violate business boundaries

Why are most Microsoft Copilot incidents entirely preventable?

Most Microsoft Copilot incidents are entirely preventable. They're not sophisticated attacks or zero-day exploits – they're the inevitable result of deploying Copilot on top of years of poor Microsoft 365 data governance and permission management across SharePoint, Teams, and OneDrive.

The data supports this reality: while 22% of organisations have unrestricted access to publicly available AI tools, 60% of IT teams report they can't see specific prompts or requests made by employees using GenAI tools. Additionally, 60% of organisations lack confidence in their ability to identify the use of unapproved AI tools in their environments.

What this looks like: Your organisation rushes to deploy Microsoft Copilot because competitors are gaining productivity advantages. IT enables Copilot for the entire organisation without first auditing who has access to what data across SharePoint sites, Teams channels, and OneDrive folders. Three months later, you're dealing with your first Copilot incident when someone in Marketing asks for "competitive analysis" and receives confidential pricing strategies from Excel, M&A discussions from Teams, and customer acquisition costs from SharePoint that were technically accessible through existing permissions but scattered across different Microsoft 365 services.

The preventable reality is that this Microsoft Copilot incident was visible months before it happened. Your SharePoint sprawl, Teams "Everyone" permissions, and legacy OneDrive access controls all pointed to exactly this type of Copilot exposure. But fixing Microsoft 365 data governance feels like infrastructure work while deploying Copilot feels like innovation.

Why this matters: Every successful Microsoft Copilot incident response starts with the same uncomfortable realisation – this incident was entirely predictable and preventable through proper Microsoft 365 permission management. Organisations that proactively secure their Microsoft 365 information architecture before Copilot deployment experience dramatically fewer incidents and much faster recovery times when Copilot incidents do occur.

The uncomfortable truth about Microsoft Copilot incident response

Traditional IR approaches assume you're investigating what an attacker did to your systems. With Microsoft Copilot incidents, you're investigating what your own Microsoft 365 environment did with your data – and that requires an entirely different approach.

The most successful organisations treat Microsoft Copilot incident response as a specialised discipline requiring dedicated tools, trained personnel familiar with Microsoft 365 architecture, and executive support. Those that try to apply traditional IR frameworks to Copilot incidents face longer detection times, higher costs, and incomplete damage assessment across their Microsoft 365 environment.

The reality is clear: organisations will experience Microsoft Copilot-related security incidents. Nearly three quarters (71%) of cybersecurity professionals believe that a cybersecurity incident is likely to disrupt their organisations' business within the next 12 to 24 months (2025 Cisco Cybersecurity Readiness Index). However, only 4% of companies have reached mature readiness levels across all cybersecurity pillars, with 70% remaining in the bottom two categories of preparedness (2025 Cisco Cybersecurity Readiness Index). The question isn't whether your Copilot deployment will cause a data exposure across Microsoft 365 – it's whether your incident response team will be ready to handle it effectively.

Microsoft Copilot incidents don't follow traditional attack patterns because they're not attacks – they're Copilot features working exactly as designed across your Microsoft 365 environment, just with unintended consequences. Your incident response framework needs to account for this fundamental difference in how Copilot operates within Microsoft 365.

Welcome to the Microsoft Copilot incident response era. Your team will need to adapt to these new challenges.

‍

TL;DR: Traditional incident response approaches fail when Microsoft Copilot causes data breaches because they're designed for external attacks, not internal AI systems that synthesise and correlate organisational data inappropriately across Microsoft 365. Copilot incidents require new forensic approaches, different containment strategies, and specialised team skills. Most Copilot incidents are preventable through proper data governance before deployment, but when they occur, organisations need frameworks that treat Copilot incidents as a unique discipline requiring dedicated tools and trained personnel.

Your incident response team just got called about a "data exposure incident involving Microsoft Copilot." The challenge? Everything they know about containing breaches doesn't apply here.

Why traditional incident response approaches fail with Microsoft Copilot

Traditional incident response assumes you can isolate compromised systems, revoke access, and contain the damage. With Microsoft Copilot, the damage is already done the moment it synthesises and shares information across your Microsoft 365 environment. You can't "un-correlate" data that's been combined from SharePoint, Teams, Outlook, and OneDrive in a single Copilot response.

What this looks like: An HR manager asks Microsoft Copilot to "analyse employee engagement across departments" and receives detailed salary information, performance reviews, and disciplinary records pulled from Excel files, SharePoint sites, and Teams conversations that were technically accessible but never actively viewed. By the time security discovers the issue three weeks later, the Copilot-generated summary has been shared with five other managers through Teams and referenced in three PowerPoint presentations.

The forensic challenge is significant. Unlike traditional breaches where attackers leave obvious traces, Microsoft Copilot incidents often look like normal Microsoft 365 operations. This challenge is compounded by the fact that 86% of business leaders with cybersecurity responsibilities reported at least one AI-related incident in the past 12 months (2025 Cisco Cybersecurity Readiness Index), yet only 49% of respondents believe employees fully understand AI-related cybersecurity threats (2025 Cisco Cybersecurity Readiness Index). An employee asking Copilot to "analyse our competitive position" and receiving confidential financial data appears as legitimate usage in Microsoft Purview audit logs.

How do you investigate a Microsoft Copilot data correlation incident?

Traditional forensic tools can't reconstruct how Microsoft Copilot accessed, processed, and synthesised information across your entire Microsoft 365 environment. When someone asks Copilot to "summarise our Q3 performance," it might correlate financial reports from SharePoint, customer complaints from Teams, operational metrics from Excel files, and strategic planning documents from OneDrive – creating a comprehensive analysis that no human would have consciously assembled.

What this looks like: Your forensic team can tell you exactly which Microsoft 365 files were accessed and when through audit logs, but they can't easily determine what sensitive insights Copilot generated by combining quarterly sales data from Excel with customer satisfaction surveys from Forms and internal strategy documents from SharePoint. Traditional digital forensics assumes you can examine compromised systems in isolation. Microsoft Copilot incidents require understanding not just what Microsoft 365 data was accessed, but how Copilot correlated and synthesised it across the organisation's environment.

The EchoLeak vulnerability (CVE-2025-32711), discovered by researchers at Aim Security, demonstrated how attackers could trigger data extraction from Microsoft 365 Copilot simply by sending an email with no user interaction required. Microsoft patched this specific vulnerability, but it demonstrates how Copilot creates entirely new attack surfaces within Microsoft 365 that traditional security monitoring cannot detect.

What should your first 60 minutes look like when a Microsoft Copilot incident hits?

Your incident response team needs to determine scope before Microsoft 365 audit logs start overwriting and Copilot-generated content gets buried in normal business communications across Teams, Outlook, and SharePoint. They need to identify which Copilot interactions are involved, what Microsoft 365 data sources Copilot accessed, and how many users potentially received inappropriate Copilot-generated content.

Critical first-hour actions for Microsoft Copilot incidents:

  • Preserve Microsoft Copilot interaction logs before they expire (Copilot audit logs retain for 180 days by default)
  • Document all Copilot-generated outputs – screenshots from Teams, chat exports from Copilot, email summaries
  • Identify affected user sessions across all Microsoft 365 services where Copilot operates
  • Determine which Microsoft 365 data sources Copilot accessed during the timeframe in question using audit logs

What this looks like: Your security team discovers that a senior executive's Microsoft Copilot session combined customer acquisition data from Dynamics with competitive intelligence reports from SharePoint and financial projections from Excel. Traditional incident response would focus on which Microsoft 365 systems were compromised. Copilot incident response must focus on what new sensitive information was created through Microsoft 365 data correlation and who received it through Teams, email, or shared documents.

Why Microsoft Copilot incidents create amplification effects across Microsoft 365

Microsoft Copilot incidents create amplification effects that traditional risk assessment models cannot capture. A single Copilot query can synthesise information from hundreds of Microsoft 365 documents, creating new sensitive data combinations that exceed the classification level of any individual SharePoint file, Teams message, or Outlook email.

The scope of AI-related incidents reflects this amplification: 43% of organisations experienced model theft or unauthorized access, 42% faced AI-enhanced social engineering attacks, and 38% dealt with data poisoning attempts in the past year.

What this looks like: A marketing manager asks Microsoft Copilot for "customer feedback analysis" and receives a summary combining customer complaints from Teams with internal pricing strategy documents from SharePoint and competitive intelligence reports from OneDrive. The Copilot-generated analysis reveals confidential pricing models and strategic plans that no human would have consciously connected across these Microsoft 365 services. By the time the incident is discovered, the summary has been shared with external consultants through Teams and referenced in a PowerPoint presentation.

This is the Microsoft Copilot amplification problem. The marketing manager had legitimate access to customer feedback data in Teams and general market research in SharePoint. But Copilot's synthesis across Microsoft 365 created a strategic intelligence document that combined information across security boundaries, revealing insights that were more sensitive than any individual Microsoft 365 data source.

How is containment different when Microsoft Copilot is your own system?

Traditional containment strategies – cutting network access, revoking credentials, isolating systems – don't work with Microsoft Copilot incidents because the exposure has already occurred through data synthesis across your Microsoft 365 environment and sharing through Teams, email, and collaborative documents.

What this looks like: Your IR team discovers that Microsoft Copilot inappropriately combined customer data from Dynamics with financial projections from Excel in response to an executive's strategic planning question in Teams. They immediately revoke the executive's Copilot license, but the Copilot-generated analysis has already been shared with the leadership team through Teams, saved in multiple SharePoint documents, and referenced in ongoing strategic PowerPoint presentations.

Recovery requires process changes across Microsoft 365, not just technical remediation:

  • Immediate access revocation: Remove Microsoft Copilot licenses for affected users while maintaining Microsoft Purview audit capabilities
  • Data re-classification: Implement emergency reviews for all Microsoft 365 information accessed during the Copilot incident
  • Communication quarantine: Identify and flag all Teams messages, Outlook emails, and SharePoint documents containing Copilot-generated summaries from the incident period

The containment paradox is this: traditional incident response focuses on stopping ongoing damage, but with Microsoft Copilot incidents, the damage occurs in the synthesis moment across Microsoft 365. Once Copilot has correlated sensitive information from SharePoint, Teams, and Outlook and shared it, containment becomes a business process challenge rather than a technical one.

What skills does your incident response team need for the Microsoft Copilot era?

Traditional IR teams focus on malware analysis and network forensics. Microsoft Copilot-ready teams need data scientists who understand Microsoft Graph API, privacy analysts familiar with Microsoft 365 data flows, and Copilot governance specialists.

The skills gap is evident: only 49% of respondents believe employees fully understand AI-related cybersecurity threats, and under half (45%) feel their company has the internal resources and expertise to conduct comprehensive AI security assessments.

What this looks like: Your current IR team can tell you exactly what Microsoft 365 files an attacker accessed and how they moved through your SharePoint environment. But when asked "what sensitive information did Microsoft Copilot create by combining quarterly sales reports from Excel with customer complaint data from Teams?" they face significant challenges. They understand technical indicators of compromise in Microsoft 365 but not the complexities of inappropriate data correlation across Copilot interactions.

Required skills for Microsoft Copilot incident response:

  • Microsoft Copilot literacy: Understanding how Copilot accesses and synthesises data across Microsoft 365 services
  • Data analysis: Ability to assess the sensitivity of Copilot-generated content combinations from multiple Microsoft 365 sources
  • Microsoft 365 investigation: Expertise in Microsoft Graph API and data flows across SharePoint, Teams, OneDrive, and Outlook
  • Business context understanding: Ability to assess when Microsoft Copilot data correlations violate business boundaries

Why are most Microsoft Copilot incidents entirely preventable?

Most Microsoft Copilot incidents are entirely preventable. They're not sophisticated attacks or zero-day exploits – they're the inevitable result of deploying Copilot on top of years of poor Microsoft 365 data governance and permission management across SharePoint, Teams, and OneDrive.

The data supports this reality: while 22% of organisations have unrestricted access to publicly available AI tools, 60% of IT teams report they can't see specific prompts or requests made by employees using GenAI tools. Additionally, 60% of organisations lack confidence in their ability to identify the use of unapproved AI tools in their environments.

What this looks like: Your organisation rushes to deploy Microsoft Copilot because competitors are gaining productivity advantages. IT enables Copilot for the entire organisation without first auditing who has access to what data across SharePoint sites, Teams channels, and OneDrive folders. Three months later, you're dealing with your first Copilot incident when someone in Marketing asks for "competitive analysis" and receives confidential pricing strategies from Excel, M&A discussions from Teams, and customer acquisition costs from SharePoint that were technically accessible through existing permissions but scattered across different Microsoft 365 services.

The preventable reality is that this Microsoft Copilot incident was visible months before it happened. Your SharePoint sprawl, Teams "Everyone" permissions, and legacy OneDrive access controls all pointed to exactly this type of Copilot exposure. But fixing Microsoft 365 data governance feels like infrastructure work while deploying Copilot feels like innovation.

Why this matters: Every successful Microsoft Copilot incident response starts with the same uncomfortable realisation – this incident was entirely predictable and preventable through proper Microsoft 365 permission management. Organisations that proactively secure their Microsoft 365 information architecture before Copilot deployment experience dramatically fewer incidents and much faster recovery times when Copilot incidents do occur.

The uncomfortable truth about Microsoft Copilot incident response

Traditional IR approaches assume you're investigating what an attacker did to your systems. With Microsoft Copilot incidents, you're investigating what your own Microsoft 365 environment did with your data – and that requires an entirely different approach.

The most successful organisations treat Microsoft Copilot incident response as a specialised discipline requiring dedicated tools, trained personnel familiar with Microsoft 365 architecture, and executive support. Those that try to apply traditional IR frameworks to Copilot incidents face longer detection times, higher costs, and incomplete damage assessment across their Microsoft 365 environment.

The reality is clear: organisations will experience Microsoft Copilot-related security incidents. Nearly three quarters (71%) of cybersecurity professionals believe that a cybersecurity incident is likely to disrupt their organisations' business within the next 12 to 24 months (2025 Cisco Cybersecurity Readiness Index). However, only 4% of companies have reached mature readiness levels across all cybersecurity pillars, with 70% remaining in the bottom two categories of preparedness (2025 Cisco Cybersecurity Readiness Index). The question isn't whether your Copilot deployment will cause a data exposure across Microsoft 365 – it's whether your incident response team will be ready to handle it effectively.

Microsoft Copilot incidents don't follow traditional attack patterns because they're not attacks – they're Copilot features working exactly as designed across your Microsoft 365 environment, just with unintended consequences. Your incident response framework needs to account for this fundamental difference in how Copilot operates within Microsoft 365.

Welcome to the Microsoft Copilot incident response era. Your team will need to adapt to these new challenges.

‍

Ben van Enckevort

CTO and Co-Founder

Ben van Enckevort is the co-founder and CTO of Metomic

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Whitepapers & Reports

Why Microsoft Purview Can't Protect Your Organization From M365 Copilot Security Risks

Microsoft Purview inadequately protects organisations from M365 Copilot security risks. Copilot amplifies permission errors by making SharePoint data easily searchable, exposing sensitive information. Purview can't detect prompt injection attacks and only reacts after breaches occur. With AI-related security incidents rising from 27% to 40%, most organisations deployed Copilot without fixing underlying permission issues. While Purview identifies problems, fixing years of poor security management remains manual work for overwhelmed teams.

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