CVE-2026-33825MicrosoftOtherApril 22, 2026

Microsoft Defender Insufficient Granularity of Access Control Vulnerability

High 7.8Actively exploitedUsed by ransomware

Description

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

What to do

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

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Details

Vendor
Microsoft
Product
Microsoft Defender
CVE
CVE-2026-33825
Affected versions
Microsoft Defender Antimalware Platform 4: from 4.0.0.0 to 4.18.26030.3011 (excluded) — fixed in 4.18.26030.3011 (from the advisory and NVD; check the exact builds in the official advisory)
CVSS score
7.8
Actively exploited
Yes, listed in the CISA Known Exploited Vulnerabilities catalog
CISA due date
May 6, 2026 (deadline for US federal agencies: a good benchmark for you too)
Source
CISA KEV – original advisory
Published
April 22, 2026

The description and the recommended action are quoted from the public advisory; severity, exploitation status and affected versions are compiled automatically from public sources and may contain errors. The vendor's original advisory prevails: check it before taking action. This information is provided without warranty and does not replace a professional assessment.

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