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CVE-2026-49798 Microsoft CVE debrief

CVE-2026-49798 is a critical vulnerability in Windows Kernel that allows an unauthorized attacker to elevate privileges locally. The vulnerability has a CVSS score of 9.3 and is classified as CRITICAL. This use-after-free issue in the Windows Kernel can be exploited by an attacker to gain elevated privileges on a local system. System administrators and users of Windows operating systems should be aware of this vulnerability and take necessary precautions to mitigate the risk. The CVE record was published on 2026-07-14T17:16:55.857Z and was last modified on 2026-07-16T15:43:36.117Z.

Vendor
Microsoft
Product
Windows 10 Version 1607
CVSS
CRITICAL 9.3
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-14
Original CVE updated
2026-07-22
Advisory published
2026-07-14
Advisory updated
2026-07-22

Who should care

System administrators and users of Windows operating systems should be aware of this vulnerability and take necessary precautions to mitigate the risk. This includes ensuring that all Windows operating systems are up-to-date, monitoring system logs for suspicious activity, and implementing additional security measures to prevent local privilege escalation. The vulnerability has a significant impact on the security of Windows operating systems, and its exploitation can result in elevated privileges.

Technical summary

The vulnerability is a use-after-free issue in the Windows Kernel, which allows an attacker to elevate privileges locally. The vulnerability has been analyzed and has a CVSS vector of CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H. This issue arises from the improper handling of memory, allowing an attacker to access memory after it has been freed. The vulnerability has a significant impact on the security of Windows operating systems, as it can be exploited by an attacker to gain elevated privileges.

Defensive priority

High

Recommended defensive actions

  • Apply the patch provided by Microsoft
  • Ensure that all Windows operating systems are up-to-date
  • Monitor system logs for suspicious activity
  • Implement additional security measures to prevent local privilege escalation
  • Review compensating controls for exposed systems while remediation is scheduled and verified

Evidence notes

The vulnerability has been reported by Microsoft and has been analyzed by the NVD. The CVE record was published on 2026-07-14T17:16:55.857Z and was last modified on 2026-07-16T15:43:36.117Z. The evidence is limited, and defenders should verify the affected scope and severity with the vendor. The vulnerability is a use-after-free issue in the Windows Kernel, and its exploitation can result in elevated privileges.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-49798 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-49798

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

  • CVE-2026-49798 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-49798

    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.