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CVE-2026-42910 Microsoft CVE debrief

CVE-2026-42910 is a HIGH severity vulnerability in Windows Hotpatch Monitoring Service that allows an authorized attacker to elevate privileges locally. The vulnerability has a CVSS score of 7.8 and was published on [cvePublishedAt](https://www.cve.org/CVERecord?id=CVE-2026-42910) 2026-06-09. The vulnerability affects multiple versions of Windows 11 and Windows Server 2025.

Vendor
Microsoft
Product
Windows Hotpatch Monitoring Service
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-09
Original CVE updated
2026-06-11
Advisory published
2026-06-09
Advisory updated
2026-06-11

Who should care

Administrators and users of affected Windows systems should apply patches to mitigate this vulnerability.

Technical summary

The vulnerability is an out-of-bounds write in Windows Hotpatch Monitoring Service, which allows an authorized attacker to elevate privileges locally. The vulnerability has been assigned a CVSS vector of CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Defensive priority

HIGH

Recommended defensive actions

  • Apply patches from Microsoft as soon as possible.
  • Review and update vulnerability management processes to ensure timely patching of affected systems.

Evidence notes

The vulnerability is based on information from the National Vulnerability Database (NVD) and Microsoft's security advisories.

Official resources

CVE-2026-42910 was published on 2026-06-09 and modified on 2026-06-11.