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CVE-2026-50658 Microsoft CVE debrief

A time-of-check time-of-use (toctou) race condition vulnerability exists in Microsoft Defender, which could allow an authorized attacker to elevate privileges locally. The vulnerability has a CVSS score of 7 and is classified as HIGH severity. This issue impacts system administrators and security teams managing Microsoft Defender installations. The vulnerability is caused by a toctou race condition, and an authorized attacker could exploit this to elevate privileges locally. The CVSS vector for this vulnerability is CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H. To mitigate, apply the latest security updates and patches for Microsoft Defender, monitor system logs for suspicious activity, and implement additional security controls to prevent local privilege escalation.

Vendor
Microsoft
Product
Microsoft Defender for Endpoint for Mac
CVSS
HIGH 7
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-14
Original CVE updated
2026-07-22
Advisory published
2026-07-14
Advisory updated
2026-07-22

Who should care

System administrators and security teams responsible for managing Microsoft Defender installations should be aware of this vulnerability and take necessary actions to mitigate it. This includes applying the latest security updates and patches, monitoring system logs for suspicious activity, and implementing additional security controls to prevent local privilege escalation.

Technical summary

The vulnerability is caused by a time-of-check time-of-use (toctou) race condition in Microsoft Defender. An authorized attacker could exploit this vulnerability to elevate privileges locally. The CVSS vector for this vulnerability is CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H. This issue has a CVSS score of 7 and is classified as HIGH severity. System administrators and security teams should be aware of this vulnerability and take necessary actions to mitigate it.

Defensive priority

High priority should be given to patching or mitigating this vulnerability, as it could allow an authorized attacker to elevate privileges locally.

Recommended defensive actions

  • Apply the latest security updates and patches for Microsoft Defender
  • Monitor system logs for suspicious activity
  • Implement additional security controls to prevent local privilege escalation
  • Conduct regular vulnerability assessments and penetration testing
  • Review and update incident response plans

Evidence notes

The CVE record was published on 2026-07-14T18:17:59.563Z and was last modified on 2026-07-22T16:35:50.343Z. The NVD entry is currently Analyzed. This vulnerability affects Microsoft Defender and has a CVSS score of 7, classified as HIGH severity. System administrators should verify their deployments and review official advisories for mitigation steps. Evidence is based on CVE and NVD entries, which may have limitations in scope and detail.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-14T18:17:59.563Z and has not been modified since then. The NVD entry is currently Analyzed.