CVE-2026-78457

Use after free in Windows Security App allows an authorized attacker to elevate privileges locally.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78457	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_11_24h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_24h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_26h1:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_26h1:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2022::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

15 Oct 2026, 00:16

Type	Values Removed	Values Added
Summary	~~(en) Use after free in Windows Security Health Service allows an authorized attacker to elevate privileges locally.~~	(en) Use after free in Windows Security App allows an authorized attacker to elevate privileges locally.

Information

Published : 2026-09-08 18:20

Updated : 2026-10-15 00:16

NVD link : CVE-2026-78457

Mitre link : CVE-2026-78457

CVE.ORG link : CVE-2026-78457

JSON object : View

Products Affected

microsoft

windows_11_25h2
windows_11_24h2
windows_11_26h1
windows_server_2022
windows_server_2025

CWE

CWE-416

Use After Free

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