CVE-2026-70578: Windows Credential Guard Elevation of Privilege Vulnerability

Severity: high (CVSS 7.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-08 · updated 2026-10-31
Weakness: CWE-122

Description

Heap-based buffer overflow in Windows Credential Guard allows an authorized attacker to elevate privileges locally.

Affected products

Microsoft Windows 10: before 10.0.19044.7725 — fixed in 10.0.19044.7725
Microsoft Windows 10: before 10.0.19045.7725 — fixed in 10.0.19045.7725
Microsoft Windows 11: before 10.0.22631.7582 — fixed in 10.0.22631.7582
Microsoft Windows 11: before 10.0.26100.9445 — fixed in 10.0.26100.9445
Microsoft Windows 11 25H2: before 10.0.26200.9445 — fixed in 10.0.26200.9445
Microsoft Windows 11 version 26H1: before 10.0.28000.2954 — fixed in 10.0.28000.2954
Microsoft Windows 10: from 10.0.19044.0 before 10.0.19044.7725 — fixed in 10.0.19044.7725
Microsoft Windows 10: from 10.0.19045.0 before 10.0.19045.7725 — fixed in 10.0.19045.7725
Microsoft Windows 11: from 10.0.22631.0 before 10.0.22631.7582 — fixed in 10.0.22631.7582
Microsoft Windows 11: from 10.0.26100.0 before 10.0.26100.9445 — fixed in 10.0.26100.9445
Microsoft Windows 11 25H2: from 10.0.26200.0 before 10.0.26200.9445 — fixed in 10.0.26200.9445
Microsoft Windows 11 version 26H1: from 10.0.28000.0 before 10.0.28000.2954 — fixed in 10.0.28000.2954

How to fix

Upgrade to a fixed version: Microsoft Windows 10 10.0.19044.7725; Microsoft Windows 10 10.0.19045.7725; Microsoft Windows 11 10.0.22631.7582; Microsoft Windows 11 10.0.26100.9445; Microsoft Windows 11 25H2 10.0.26200.9445; Microsoft Windows 11 version 26H1 10.0.28000.2954; Microsoft Windows 10 10.0.19044.7725; Microsoft Windows 10 10.0.19045.7725; Microsoft Windows 11 10.0.22631.7582; Microsoft Windows 11 10.0.26100.9445; Microsoft Windows 11 25H2 10.0.26200.9445; Microsoft Windows 11 version 26H1 10.0.28000.2954. Check the vendor advisory for mitigations.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70578

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