Microsoft Defender Insufficient Granularity of Access Control Vulnerability. Actively exploited: CISA added this vulnerability to its Known Exploited Vulnerabilities catalog on 22/04/2026. Patch affected systems as an emergency. It is known to be used in ransomware campaigns.
| Package | Affected versions | Patched versions |
|---|---|---|
| defender antimalware platform | < 4.18.26030.3011 | 4.18.26030.3011 |
Insufficient granularity of access control in Microsoft Defender allows an authorized attacker to elevate privileges locally.
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