CVE-2026-45498

Microsoft Defender Denial of Service Vulnerability

Microsoft — Defender

Added to KEV catalog: 20 May 2026
Federal remediation due date: 3 June 2026

CISA Description

Microsoft Defender contains an unspecified vulnerability that allows for denial of service.

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/en-US/vulnerability/CVE-2026-45498 ; https://nvd.nist.gov/vuln/detail/CVE-2026-45498

View on NVD View on MITRE CVE View full CISA catalog

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