Caesar AI Atlas
Бухгалтерия
2025-07-04Кейс #50

Уязвимость Microsoft 365 Copilot, как утверждается, позволяла получать доступ к файлам без записи в журнал аудита

Описание инцидента

Уязвимость в Microsoft 365 Copilot, как сообщалось, позволяла пользователям получать доступ к файлам и кратко излагать их содержимое без создания записей в журнале аудита, что, как утверждается, подрывало прослеживаемость и соблюдение требований. Исследователь безопасности Zack Korman сообщил о проблеме Microsoft, которая, как сообщалось, классифицировала её как «важную» и исправила 17 августа 2025 года, но, как сообщалось, решила не уведомлять клиентов и не присваивать CVE.

Комплайенс-досье

Практическое управление корпоративными рисками и регламенты

Влияние на бизнес и риски МСБ

The security vulnerability in Microsoft 365 Copilot—which allowed it to access and read internal company files, spreadsheets (such as payroll and taxes), and emails without registering a 'read' event in the Microsoft 365 Purview audit log—exposed organizations to extreme insider threat risks. Insiders could use Copilot to exfiltrate sensitive files without leaving any trace in the logs. This directly violates data logging compliance frameworks (such as SOC 2, HIPAA, and ISO 27001), rendering data exfiltration untraceable and exposing the firm to massive regulatory fines and loss of client trust. Regulatory Impact Alignment: Financial audits, transaction tracking, and internal reporting algorithms must comply with Sarbanes-Oxley (SOX) Section 404 and AICPA SOC 2 Type II regulations. Accounting teams must prevent data leakage by isolating sensitive financial logs from public generative AI models.

Главный комплайенс-урок

Deploying generative search and AI assistants over internal enterprise document repositories often bypasses traditional read-event logging and file access monitors. Organizations cannot assume that existing enterprise security integrations automatically cover generative AI interactions. Logging architectures must be thoroughly verified before deployment. Compliance Audit Standards: For detailed verification audits, this case maps directly under Sarbanes-Oxley Act (SOX) Section 404 & AICPA SOC 2 Type II Safeguards. Systems deploying similar AI features must maintain dynamic security logs and hold systematic compliance records.

Пошаговый план внедрения регламентов

  • 1Verify Purview AI Logging: Conduct exhaustive security reviews of Microsoft Purview and Copilot logging integrations to ensure all AI read events are recorded in audit logs.
  • 2Least-Privilege Directory Blocks: Enforce strict least-privilege permission models, preventing Copilot from indexing or searching folders containing sensitive financial or payroll data.
  • 3Simulate Insider Queries: Perform regular automated testing simulating insider query attempts to verify that all access attempts generate standard audit logs.
  • 4Deploy DLP exfiltration blockers: Deploy Data Loss Prevention (DLP) tools to monitor, restrict, and log the exfiltration of sensitive documents retrieved via generative AI.
  • 5Deterministic Audit Trail: Generate complete, cryptographically signed, and chronological audit trails for every automated transaction analysis.
  • 6Vpc Network Isolation: Restrict all corporate ledger evaluations to network-isolated Private Virtual Clouds (VPCs) without public internet hooks.
  • 7Leakage Monitoring: Configure active data loss prevention (DLP) alerts to immediately block the paste or upload of proprietary files to external LLM APIs.

Комментарий эксперта по комплайенсу

Профессиональный комплаенс-анализ инцидента

Copilot makes internal file access incredibly easy. If your audit logs don't record what the AI reads on behalf of a user, you are completely blind to insider theft and data breaches. Verify your AI logging integrations before you expose your document repositories.

Терминология и нюансы глоссария ИИ

AI Compliance FAQ

Critical answers regarding AI compliance, auditing, and organizational risks

QWhat security vulnerability was discovered in Microsoft 365 Copilot?

A critical indexing bug allowed Copilot to read and extract information from internal company files (such as payroll spreadsheets) without writing a corresponding 'file read' event into the Microsoft Purview audit logs, rendering access untraceable.

QWhy are standard corporate directories vulnerable to Copilot indexing?

Copilot indexes all files the user has permission to view. Many firms have loose folder configurations where files are shared widely, allowing Copilot to surface sensitive financial records in chat answers.

QHow do firms maintain SOC 2 compliance while using Copilot?

Firms must perform a least-privilege access audit (Shadow IT check), configure strict folder blocks preventing Copilot indexing of payroll directories, and verify that all generative reads produce audit logs.

Участники инцидента

Кто развернул систему

Microsoft

Кто разработал систему

Microsoft

Кто пострадал

корпоративные клиенты Microsoft 365 Copilotорганизации, полагающиеся на журналы аудита для соблюдения требований и безопасности

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