Improper input validation in Windows Server Update Service allows an unauthorized attacker to execute code over a network.
References
| Link | Resource |
|---|---|
| https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20856 | Vendor Advisory |
Configurations
Configuration 1 (hide)
|
History
15 Jan 2026, 15:20
| Type | Values Removed | Values Added |
|---|---|---|
| First Time |
Microsoft windows 11 24h2
Microsoft windows 11 25h2 Microsoft windows Server 2022 Microsoft Microsoft windows Server 2016 Microsoft windows Server 2022 23h2 Microsoft windows 10 1607 Microsoft windows Server 2012 Microsoft windows 10 1809 Microsoft windows 10 21h2 Microsoft windows 11 23h2 Microsoft windows 10 22h2 Microsoft windows Server 2019 Microsoft windows Server 2025 |
|
| References | () https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20856 - Vendor Advisory | |
| CPE | cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:* cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:* cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:* cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:* cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:* cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* |
13 Jan 2026, 18:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-01-13 18:16
Updated : 2026-01-15 15:20
NVD link : CVE-2026-20856
Mitre link : CVE-2026-20856
CVE.ORG link : CVE-2026-20856
JSON object : View
Products Affected
microsoft
- windows_server_2025
- windows_10_1809
- windows_server_2012
- windows_10_22h2
- windows_server_2022_23h2
- windows_server_2019
- windows_server_2022
- windows_10_1607
- windows_11_24h2
- windows_server_2016
- windows_11_23h2
- windows_11_25h2
- windows_10_21h2
CWE
CWE-20
Improper Input Validation