CVE-2026-45498

high KEV

Published 2026-05-20 · Modified 2026-05-20

CVSS v3

7.5

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS v2

—

VIR risk

9.0

Description

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

CISA KEV

Vendor: Microsoft
Product: Defender
Due date: 2026-06-03

Predictions

Exploit likelihood

99%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

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

vendor Authored 2026-05-27

Vendor advisory: secure@microsoft.com — https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45498

Exploits

Application impact

Vendor	Product	Versions	Fixed
microsoft	defender_antimalware_platform	`{"endExcluding":"4.18.26040.7"}`	`4.18.26040.7`

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45498
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-45498
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-45498 ; https://nvd.nist.gov/vuln/detail/CVE-2026-45498

CWEs

CWE-400

Verify integrity in audit chain (admin only). AS-IS.