Vulnerability record

CVE-2026-33825

Microsoft Defender Insufficient Granularity of Access Control Vulnerability

Severity: HighExploitation: Exploitation confirmedCISA KEV Used by ransomware
What should I do?

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Defender, fix it now.

CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

US federal civilian agencies must remediate by May 6, 2026.

Patch status

No official fix confirmed yet

Until a fix ships, follow the vendor's mitigations and CISA's required action, limit exposure of affected systems, and watch this record for a patch.

Description

Insufficient granularity of access control in Microsoft Defender allows an authorized attacker to elevate privileges locally.

Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.

Affected products

Products affected by this vulnerability, with versions and the source of each entry
ProductVendorSource
DefenderMicrosoftKEV

Sources: KEV = CISA Known Exploited Vulnerabilities catalog. Version details have not been published yet.

Intelligence timeline

Developments from the last 30 days, newest first.

No developments recorded for CVE-2026-33825 in the last 30 days.

1 earlier event is available with a subscription. See plans.

Coverage

We have not published a story about this vulnerability yet.

References

  • msrc.microsoft.com https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33825
  • nvd.nist.gov https://nvd.nist.gov/vuln/detail/CVE-2026-33825
  • cisa.gov https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-33825
  • huntress.com https://www.huntress.com/blog/nightmare-eclipse-intrusion