CVE Watch—

CVE-2026-45498

Microsoft Defender Denial of Service Vulnerability

CVSS

—

No CVSS

EPSS

63.1%

p99

KEV

YES

May 20, 2026

Exploit Today

0-100

Published: — · Last modified: —

EPSS · 30d

63.1%EPSS · 30 days63.1%

2026-06-302026-07-16

KEV catalog record

Product

Microsoft / Defender

Vulnerability

Microsoft Defender Denial of Service Vulnerability

Added to KEV

May 20, 2026

Remediate by

Jun 3, 2026

Known ransomware use

Summary 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

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