PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-56650 Microsoft CVE debrief

CVE-2026-56650 is a high-severity vulnerability in Windows Network File System that allows an authorized attacker to elevate privileges locally. The vulnerability has a CVSS score of 7.8 and is classified as HIGH. Microsoft has released a patch for this vulnerability. The vulnerability is caused by a heap-based buffer overflow condition due to improper handling of network file system requests. System administrators and security teams should be aware of this vulnerability and take necessary actions to mitigate it.

Vendor
Microsoft
Product
Windows Network File System
CVSS
HIGH 7.8
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 security teams responsible for Windows Network File System should be aware of this vulnerability and take necessary actions to mitigate it. They should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. They should also plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.

Technical summary

A heap-based buffer overflow vulnerability exists in Windows Network File System, which allows an authorized attacker to elevate privileges locally. The vulnerability is caused by improper handling of network file system requests, leading to a buffer overflow condition. An attacker can exploit this vulnerability to gain elevated privileges on the affected system. Microsoft has released a patch to fix this vulnerability.

Defensive priority

High

Recommended defensive actions

  • Apply the patch released by Microsoft to fix the vulnerability.
  • Implement compensating controls, such as monitoring and exception tracking, to detect and respond to potential attacks.
  • Conduct inventory checks to ensure that all affected systems are identified and patched.
  • Review compensating controls for exposed systems while remediation is scheduled and verified.
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

The CVE record was published on 2026-07-14T18:18:32.100Z and was last modified on 2026-07-17T13:29:22.827Z. The NVD entry is currently Analyzed. This vulnerability affects Windows Network File System, allowing an authorized attacker to elevate privileges locally. The CVSS score is 7.8, classified as HIGH. Microsoft has released a patch for this vulnerability. Evidence is limited to CVE and NVD details, with no additional information available.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-56650 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-56650

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

  • CVE-2026-56650 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-56650

    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.