Microsoft’s agentic security system found four critical Windows RCE flaws

Help Net Security

Overview

Microsoft's new agentic security system has identified 16 vulnerabilities in the Windows networking and authentication stack, including four critical remote code execution (RCE) flaws. Among these, CVE-2026-40361 and CVE-2026-40364 are particularly concerning due to their higher likelihood of being exploited by attackers. These vulnerabilities could allow unauthorized users to execute arbitrary code on affected systems, potentially leading to severe security breaches. Organizations using Microsoft Windows should prioritize addressing these vulnerabilities to protect their systems from potential exploitation, especially as the threat landscape evolves. The discovery of these flaws underscores the importance of continuous security assessments in software development and deployment.

Key Takeaways

  • Affected Systems: Microsoft Windows operating systems, particularly those utilizing the networking and authentication stack.
  • Action Required: Microsoft is expected to release patches to address these vulnerabilities.
  • Timeline: Newly disclosed

Original Article Summary

Microsoft responded to growing competition in AI security by announcing that its new agentic security system helped researchers discover 16 new vulnerabilities in the Windows networking and authentication stack, including four critical remote code execution (RCE) vulnerabilities. MDASH architecture diagram (Source: Microsoft) Two of the four flaws — CVE-2026-40361 and CVE-2026-40364 — were deemed by Microsoft to be more likely to be exploited. The multi-model agentic scanning harness, codenamed MDASH, was built by Microsoft’s Autonomous … More → The post Microsoft’s agentic security system found four critical Windows RCE flaws appeared first on Help Net Security.

Impact

Microsoft Windows operating systems, particularly those utilizing the networking and authentication stack.

Exploitation Status

The exploitation status is currently unknown. Monitor vendor advisories and security bulletins for updates.

Timeline

Newly disclosed

Remediation

Microsoft is expected to release patches to address these vulnerabilities. Users should ensure that their systems are updated with the latest security patches as soon as they become available. Additionally, organizations should conduct thorough vulnerability assessments and consider implementing security measures to mitigate potential risks until patches are applied.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to Windows, CVE, Microsoft, and 2 more.

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