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CVE-2026-54991 Microsoft CVE debrief

CVE-2026-54991 is a high-severity vulnerability in the Windows USB Print Driver that allows an authorized attacker to elevate privileges locally due to a race condition. The vulnerability has a CVSS score of 7.8 and is classified as HIGH. Microsoft has released a patch for this vulnerability. The vulnerability affects Windows 11 24H2, 25H2, 26H1, and Windows Server 2025. The vulnerability is caused by a race condition in the Windows USB Print Driver, which allows an authorized attacker to elevate privileges locally. System administrators and users of Windows 11 and Windows Server 2025 should be aware of this vulnerability and take steps to mitigate it.

Vendor
Microsoft
Product
Windows 11 Version 24H2
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-14
Original CVE updated
2026-07-20
Advisory published
2026-07-14
Advisory updated
2026-07-20

Who should care

System administrators and users of Windows 11 24H2, 25H2, 26H1, and Windows Server 2025 should be aware of this vulnerability and take steps to mitigate it. The vulnerability has a CVSS score of 7.8 and is classified as HIGH. The vulnerability allows an authorized attacker to elevate privileges locally due to a race condition. System administrators should review the official advisory and CVE record to validate affected scope, severity, and vendor guidance.

Technical summary

The vulnerability is caused by a race condition in the Windows USB Print Driver, which allows an authorized attacker to elevate privileges locally. The vulnerability affects Windows 11 24H2, 25H2, 26H1, and Windows Server 2025. The Windows USB Print Driver is a critical component that allows for printing functionality in Windows operating systems. An authorized attacker can exploit this vulnerability to elevate privileges locally due to a race condition. Microsoft has released a patch for this vulnerability.

Defensive priority

High

Recommended defensive actions

  • Apply the patch released by Microsoft
  • Ensure that the Windows USB Print Driver is up to date
  • Monitor system logs for suspicious activity
  • Implement additional security measures to prevent privilege escalation
  • Review compensating controls for exposed systems while remediation is scheduled and verified

Evidence notes

The vulnerability is documented in the CVE record and the NVD detail page. Microsoft has released a patch for this vulnerability. The Windows USB Print Driver is a critical component that allows for printing functionality in Windows operating systems. An authorized attacker can exploit this vulnerability to elevate privileges locally due to a race condition. The CVE record was published on 2026-07-14T17:17:06.720Z and has not been modified since then. The NVD entry is currently Analyzed. To verify the vulnerability, defenders should review the official advisory and CVE record. The vulnerability affects Windows 11 24H2, 25H2, 26H1, and Windows Server 2025.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-54991 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-54991

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-54991 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-54991

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.