CVE-2026-33825 Known ransomware use

Microsoft Defender Insufficient Granularity of Access Control Vulnerability

Microsoft — Defender

Added to KEV catalog: 22 April 2026
Federal remediation due date: 6 May 2026
Weakness classification (CWE): CWE-1220

CISA Description

Microsoft Defender contains an insufficient granularity of access control vulnerability that could allow an authorized attacker to escalate privileges locally.

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.

Notes

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33825 ; https://nvd.nist.gov/vuln/detail/CVE-2026-33825

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