CVE-2026-105733: Windows Hyper-V Remote Code Execution Vulnerability
Improper access control in Windows Hyper-V allows an authorized attacker to execute code locally.
- Published by source
- 2026-10-13
- First seen by Reality Radar
- 2026-10-22
- Last verified
- 2026-10-22
Affected
- Manufacturer
- Microsoft
- Products
- Windows 10 Version 21H2 Windows 10 Version 22H2 Windows Server 2022 Windows 11 Version 23H2 Windows 11 Version 24H2 Windows 11 Version 25H2 Windows 11 Version 26H2 Windows Server 2025 Windows 11 version 26H1 Windows 11 Version 26H1
- CPE
- cpe:2.3:o:microsoft:windows_10_21H2:*:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_10_22H2:*:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_10_21H2:*:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10_22H2:*:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*
Whether your exact unit is affected depends on the model, serial number and region in the official notice.
What the official notice says
Risk: Critical — Remote Code Execution
Remedy / actions:
- Install the security update: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB5126657
Is this affecting you?
Add what you own or use and Reality Radar will tell you when official changes match it — with evidence and next steps.
Sources
- Microsoft Security Update Guide (MSRC) Tier A · official published 2026-10-13
Evidence ledger
Every piece of evidence we store is appended to a public hash chain, so later edits are detectable. Anyone can re-verify it.
| Entry | Kind | Observed | Evidence hash | Entry hash |
|---|---|---|---|---|
| #105 | new | 2026-10-22 | 7e156ab22ee5…221954 | 7b6a39d6f842…d7f965 |
Chain head: #1076 8ad5adc30b9b…88ce20