CVE-2026-20837

Heap-based buffer overflow in Windows Media allows an unauthorized attacker to execute code locally.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20837	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_10_1809:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1809:::::::x86:*
	cpe:2.3:o:microsoft:windows_10_21h2::::::::
	cpe:2.3:o:microsoft:windows_10_22h2::::::::
	cpe:2.3:o:microsoft:windows_11_23h2::::::::
	cpe:2.3:o:microsoft:windows_11_24h2::::::::
	cpe:2.3:o:microsoft:windows_11_25h2::::::::
	cpe:2.3:o:microsoft:windows_server_2019::::::::
	cpe:2.3:o:microsoft:windows_server_2022::::::::
	cpe:2.3:o:microsoft:windows_server_2022_23h2::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

No history.

Information

Published : 2026-01-13 18:16

Updated : 2026-01-15 15:08

NVD link : CVE-2026-20837

Mitre link : CVE-2026-20837

CVE.ORG link : CVE-2026-20837

JSON object : View

Products Affected

microsoft

windows_10_1809
windows_server_2022_23h2
windows_server_2022
windows_11_24h2
windows_server_2025
windows_server_2019
windows_10_21h2
windows_10_22h2
windows_11_25h2
windows_11_23h2

CWE

CWE-122

Heap-based Buffer Overflow

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