CVE-2026-6726: MITRE: CVE-2026-6726 TPM 2.0 Improper Object Slot Reuse

CVE-2026-6726 is a spoofing vulnerability in MITRE, rated Important by Microsoft, with a CVSS 3.1 base score of 7.9 (High). An attacker can exploit it by an attacker with local access, with high privileges and without user interaction. Microsoft has not reported exploitation in the wild and rates exploitation as less likely. The EPSS model estimates a 0.19% probability of exploitation activity in the next 30 days, higher than 9% of all scored vulnerabilities. Microsoft released the fix on 11 August 2026 in the August 2026 Patch Tuesday, delivered through 14 security updates (KB5120238, KB5120242, KB5120229, KB5123303 and more). It affects 30 products in 3 product families (Windows, ESU, Azure).

Key facts

CVE ID: CVE-2026-6726
Severity: High CVSS 7.9
Microsoft severity: Important
Impact: Spoofing
Exploited in the wild: No
Publicly disclosed: No
Exploitation likelihood: Less Likely
Weakness: CWE-704
EPSS: 0.19% (percentile 9%)
CISA KEV: Not listed
Released: 11 August 2026
Last updated: 11 August 2026
Patch Tuesday: August 2026 Patch Tuesday
Product families: Windows, ESU, Azure

CVSS score and vector

Microsoft scores CVE-2026-6726 at 7.9 (temporal 6.9) using CVSS 3.1. Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N/E:U/RL:O/RC:C

Metric	Value
Attack vector	Local
Attack complexity	Low
Privileges required	High
User interaction	None
Scope	Changed
Confidentiality impact	High
Integrity impact	High
Availability impact	None
Exploit code maturity	Unproven
Remediation level	Official fix
Report confidence	Confirmed

Description

CVE-2026-6726 is a Spoofing vulnerability in the TPM 2.0 reference implementation involving improper object-slot reuse. MITRE assigned this CVE on behalf of the Trusted Computing Group. This document incorporates updates to Microsoft Windows that address this vulnerability.

Please see CVE-2026-6726 for more information.

Frequently asked questions (Microsoft)

Do I need to do anything additional in order to be protected from this vulnerability?

Yes, you will need to install the following packages:

Windows 11 Enterprise, versions 25H2 and 24H2: KB5123607
Windows 11 Enterprise, versions 25H2 and 24H2 — Additional update for devices where the Pluton security processor has been configured as the TPM: KB5123273 (restart required)
Windows Server 2022: KB5123303 (restart required)

Affected products (30)

Windows

Product	Security update	Type	Fixed build	Restart
Windows 10 Version 1809 for 32-bit Systems	KB5120238	Security Update	10.0.17763.9121	Yes
Windows 10 Version 1809 for x64-based Systems	KB5120238	Security Update	10.0.17763.9121	Yes
Windows Server 2019	KB5120238	Security Update	10.0.17763.9121	Yes
Windows Server 2019 (Server Core installation)	KB5120238	Security Update	10.0.17763.9121	Yes
Windows Server 2022	KB5120242 KB5120229 KB5123303	Security Update Security Hotpatch Update Security Update	10.0.20348.5499 10.0.20348.5440 10.0.20348.5499	Yes Yes Yes
Windows Server 2022 (Server Core installation)	KB5120242 KB5120229 KB5123303	Security Update Security Hotpatch Update Security Update	10.0.20348.5499 10.0.20348.5440 10.0.20348.5499	Yes Yes Yes
Windows 10 Version 21H2 for 32-bit Systems	KB5120249	Security Update	10.0.19044.7663	Yes
Windows 10 Version 21H2 for ARM64-based Systems	KB5120249	Security Update	10.0.19044.7663	Yes
Windows 10 Version 21H2 for x64-based Systems	KB5120249	Security Update	10.0.19044.7663	Yes
Windows Server 2025 (Server Core installation)	KB5120233 KB5120228	Security Update Security Hotpatch Update	10.0.26100.33296 10.0.26100.33222	Yes Yes
Windows 11 Version 25H2 for ARM64-based Systems	KB5121003 KB5120994 KB5123607 KB5123273	Security Update Security Hotpatch Update Security Hotpatch Update Security Update	10.0.26200.9168 10.0.26200.9106 10.0.26200.9165 10.0.26200.9165	Yes Yes Yes Yes
Windows 11 Version 25H2 for x64-based Systems	KB5121003 KB5120994 KB5123607 KB5123273	Security Update Security Hotpatch Update Security Hotpatch Update Security Update	10.0.26200.9168 10.0.26200.9106 10.0.26200.9165 10.0.26200.9165	Yes Yes Yes Yes
Windows 11 Version 23H2 for ARM64-based Systems	KB5120240	Security Update	10.0.22631.7517	Yes
Windows 11 Version 23H2 for x64-based Systems	KB5120240	Security Update	10.0.22631.7517	Yes
Windows 11 Version 24H2 for ARM64-based Systems
Windows 11 Version 24H2 for x64-based Systems
Windows Server 2025	KB5120233 KB5120228	Security Update Security Hotpatch Update	10.0.26100.33296 10.0.26100.33222	Yes Yes
Windows 11 version 26H1 for x64-based Systems	KB5121000	Security Update	10.0.28000.2704	Yes
Windows 11 Version 26H1 for ARM64-based Systems	KB5121000	Security Update	10.0.28000.2704	Yes
Windows 10 Version 1607 for 32-bit Systems	KB5120418	Security Update	10.0.14393.9418	Yes
Windows 10 Version 1607 for x64-based Systems	KB5120418	Security Update	10.0.14393.9418	Yes

ESU

Product	Security update	Type	Fixed build	Restart
Windows 10 Version 22H2 for x64-based Systems
Windows 10 Version 22H2 for ARM64-based Systems
Windows 10 Version 22H2 for 32-bit Systems

Azure

Product	Security update	Type	Fixed build	Restart
Azure Confidential Compute VM SKU DCasv5/DCadsv5
Azure Confidential Compute VM SKU ECasv5/ECadsv5
Azure Confidential Compute VM SKU DCasv6/DCadsv6
DCesv6-series Azure VM
Azure Confidential Compute VM SKU ECasv6/ECadsv6
Ecesv6-series Azure VM

Security updates (14)

KB5120238 (Security Update)
KB5120242 (Security Update)
KB5120229 (Security Hotpatch Update)
KB5123303 (Security Update)
KB5120249 (Security Update)
KB5120233 (Security Update)
KB5120228 (Security Hotpatch Update)
KB5121003 (Security Update)
KB5120994 (Security Hotpatch Update)
KB5123607 (Security Hotpatch Update)
KB5123273 (Security Update)
KB5120240 (Security Update)
KB5121000 (Security Update)
KB5120418 (Security Update)

NIST NVD data

NVD status: Awaiting Analysis
NVD CVSS: 7.9 (HIGH)
NVD weakness: CWE-704
Published to NVD: 11 August 2026
NVD last modified: 24 October 2026

References

Acknowledgments

Anonymous

Revision history

Version	Date	Description
1.0	11 August 2026	Information published.