CVE-2026-21236HighMicrosoft CVSS 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Microsoft security update for CVE-2026-21236 — Windows

Published
February 10, 2026
Last Modified
—

🔗 CVE IDs covered (1)

CVE-2026-21236 →

📋 Microsoft's advisory

EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21236. This page also shows what EchelonGraph holds for CVE-2026-21236, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.

🎯 Affected products31

  • Windows 10 Version 1607 for 32-bit Systems
  • Windows 10 Version 1607 for x64-based Systems
  • Windows 10 Version 1809 for 32-bit Systems
  • Windows 10 Version 1809 for x64-based Systems
  • Windows 10 Version 21H2 for 32-bit Systems
  • Windows 10 Version 21H2 for ARM64-based Systems
  • Windows 10 Version 21H2 for x64-based Systems
  • Windows 10 Version 22H2 for 32-bit Systems
  • Windows 10 Version 22H2 for ARM64-based Systems
  • Windows 10 Version 22H2 for x64-based Systems
  • Windows 11 Version 23H2 for ARM64-based Systems
  • Windows 11 Version 23H2 for x64-based Systems
  • Windows 11 Version 24H2 for ARM64-based Systems
  • Windows 11 Version 24H2 for x64-based Systems
  • Windows 11 Version 25H2 for ARM64-based Systems
  • Windows 11 Version 25H2 for x64-based Systems
  • Windows 11 Version 26H1 for ARM64-based Systems
  • Windows 11 version 26H1 for x64-based Systems
  • Windows Server 2012
  • Windows Server 2012 (Server Core installation)
  • Windows Server 2012 R2
  • Windows Server 2012 R2 (Server Core installation)
  • Windows Server 2016
  • Windows Server 2016 (Server Core installation)
  • Windows Server 2019
  • Windows Server 2019 (Server Core installation)
  • Windows Server 2022
  • Windows Server 2022 (Server Core installation)
  • Windows Server 2022, 23H2 Edition (Server Core installation)
  • Windows Server 2025
  • +1 more not shown

✅ Updates Microsoft lists: 14 KB articles

17 rows: one per KB article or update, update type and fixed build. Their details are on Microsoft's advisory.

KB articleUpdateFixed build
KB5077179Security Update10.0.28000.1575
KB5075904Security Update10.0.17763.8389
KB5075906Security Update10.0.20348.4773
KB5075943Security Hotpatch Update10.0.20348.4711
KB5075912Security Update10.0.19044.6937
KB5075912Security Update10.0.19045.6937
KB5075899Security Update10.0.26100.32370
KB5075942Security Hotpatch Update10.0.26100.32313
KB5077181Security Update10.0.26200.7840
KB5077212Security Hotpatch Update10.0.26200.7781
KB5075941Security Update10.0.22631.6649
KB5075897Security Update10.0.25398.2149
KB5077181Security Update10.0.26100.7840
KB5077212Security Hotpatch Update10.0.26100.7781
KB5075999Security Update10.0.14393.8868
KB5075971Monthly Rollup6.2.9200.25923
KB5075970Monthly Rollup6.3.9600.23022

🧭 EchelonGraph on CVE-2026-21236

EchelonGraph score
7.8 HIGH
CISA KEV
Not listed
Fix status
A fix is available — apply it.

Description from the CVE record (CVE.org), as published by its numbering authority

Heap-based buffer overflow in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

Published by Microsoft Corporation, the CVE Numbering Authority that assigned CVE-2026-21236, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).

🔗 References (29)