AdvisoriesCVE-2026-45498

Microsoft Defender Denial of Service Vulnerability

MicrosoftDefenderAdded May 20, 2026

CISA Known Exploited Vulnerabilities Data

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.

CISA Due Date

June 3, 2026 (federal agency requirement)

Known Ransomware Campaign Use

Unknown

Notes

https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-45498 ; https://nvd.nist.gov/vuln/detail/CVE-2026-45498

External References

View on CISA KEV View CVE-2026-45498 on NVD Search MITRE ATT&CK

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Data sourced from the CISA Known Exploited Vulnerabilities catalog. CISA does not endorse any commercial product or service.