PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-77489 Microsoft CVE debrief

A null pointer dereference vulnerability in the Windows Biometric Service allows an authorized attacker to elevate privileges locally. This HIGH severity vulnerability, with a CVSS score of 7.8, was published on 2026-09-08T18:20:34.657Z and last modified on 2026-09-11T20:07:45.743Z. The vulnerability exists in the Windows Biometric Service and can be exploited by an authorized attacker to elevate privileges locally. The affected products include various versions of Windows 10, Windows 11, and Windows Server. Defenders responsible for Windows systems, especially those with local access to sensitive data or services, should assess exposure and prioritize patching. The CVE Program and

Vendor
Microsoft
Product
Windows 10 Version 1607
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-09-08
Original CVE updated
2026-09-11
Advisory published
2026-09-08
Advisory updated
2026-09-11

Who should care

Defenders responsible for Windows systems, especially those with local access to sensitive data or services, should assess exposure and prioritize patching.

Why it matters

CVE-2026-77489 is a HIGH severity vulnerability in Windows Biometric Service that allows an authorized attacker to elevate privileges locally. Defenders should prioritize patching, especially for high-risk systems, and verify affected versions and exposure.

  • Potential elevation of privileges by authorized attackers with local access.
  • Increased risk for systems with sensitive data or services exposed locally.
  • Requires verification of affected versions and exposure in the environment.

Technical summary

The vulnerability exists in the Windows Biometric Service and can be exploited by an authorized attacker to elevate privileges locally. The affected products include various versions of Windows 10, Windows 11, and Windows Server. This HIGH severity vulnerability has a CVSS score of 7.8 and was published on 2026-09-08T18:20:34.657Z. Defenders should prioritize patching this vulnerability, especially for systems with high-risk exposure, such as those with local access to sensitive data or services. The vulnerability is described as a null pointer dereference in the

Defensive priority

Defenders should prioritize patching this vulnerability, especially for systems with high-risk exposure, such as those with local access to sensitive data or services.

Recommended defensive actions

  • Apply patches from Microsoft for the affected Windows versions.
  • Conduct a thorough inventory of Windows systems to identify potential exposure.
  • Verify that local access controls and authentication mechanisms are properly configured.

Evidence notes

The vulnerability is described as a null pointer dereference in the Windows Biometric Service, which could allow an authorized attacker to elevate privileges locally. The CVE Program and NVD provide official records and assessments of this vulnerability.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-77489 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-77489

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

  • CVE-2026-77489 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-77489

    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.