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PatchSiren cyber security CVE debrief

CVE-2026-49787 Microsoft CVE debrief

A vulnerability in Windows HTTP.sys allows an unauthorized attacker to deny service over a network due to allocation of resources without limits or throttling. This issue affects Windows operating systems, and system administrators should be aware of the potential impact on their environments. The vulnerability can be exploited by sending a specially crafted request that causes the system to allocate excessive resources, leading to a denial of service.

Vendor
Microsoft
Product
Windows 10 Version 1607
CVSS
HIGH 7.5
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 reviewing system configurations, monitoring network traffic, and applying patches provided by Microsoft.

Technical summary

The vulnerability exists in Windows HTTP.sys, which is responsible for handling HTTP requests. An attacker can exploit this vulnerability by sending a specially crafted request that causes the system to allocate excessive resources, leading to a denial of service. The vulnerability can be mitigated by applying patches provided by Microsoft and implementing network segmentation and isolation.

Defensive priority

High

Recommended defensive actions

  • Apply patches provided by Microsoft
  • Implement network segmentation and isolation
  • Monitor system resources and network traffic
  • Use a web application firewall
  • Keep Windows and software up-to-date

Evidence notes

The CVE record was published on 2026-07-14T17:16:54.053Z and was last modified on 2026-07-20T13:28:31.683Z. The source details are limited, and further verification is needed to confirm affected scope and severity. Defenders should review the official CVE record and vendor advisory for more information.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-49787 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-49787

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

  • CVE-2026-49787 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-49787

    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.