CVE-2026-58540

Windows Installer Elevation of Privilege Vulnerability

Published Jul 14, 2026 CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

Description

Improper authorization in Windows Installer allows an authorized attacker to elevate privileges locally.

Analysis

Technical impact

This vulnerability is an improper authorization flaw in Windows Installer that permits an attacker who already has local access to elevate their privileges. The weakness, identified as CWE-285, allows a non‑privileged user to gain administrative rights without any additional authentication or network exploitation.

Affected Systems

The flaw affects a range of Microsoft Windows operating systems. All Windows 10 releases from version 1607 through 22H2 are impacted, as are Windows 11 releases 24H2, 25H2 and 26H1. Additionally, Windows Server editions from 2012 through 2025, including core and standard installations, are vulnerable. The issue resides in the Windows Installer component across these releases.

Risk and Exploitability

The CVSS score of 7.8 denotes a moderate‑to‑high severity. The EPSS score of less than 1% indicates that exploitation is currently rare. The vulnerability is not listed in the CISA KEV catalog. The attack requires local user privileges; the attacker must already possess some level of local access to trigger the improper authorization check during installation or execution of MSI packages.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Microsoft

Windows 10 Version 1607

affected

Version	Status	Constraints
`10.0.14393.0`	affected	< 10.0.14393.9339

Microsoft

Windows 10 Version 1809

affected

Version	Status	Constraints
`10.0.17763.0`	affected	< 10.0.17763.9020

Microsoft

Windows 10 Version 21H2

affected

Version	Status	Constraints
`10.0.19044.0`	affected	< 10.0.19044.7548

Microsoft

Windows 10 Version 22H2

affected

Version	Status	Constraints
`10.0.19045.0`	affected	< 10.0.19045.7548

Microsoft

Windows 11 Version 24H2

affected

Version	Status	Constraints
`10.0.26100.0`	affected	< 10.0.26100.8875

Microsoft

Windows 11 Version 25H2

affected

Version	Status	Constraints
`10.0.26200.0`	affected	< 10.0.26200.8875

Microsoft

Windows 11 version 26H1

affected

Version	Status	Constraints
`10.0.28000.0`	affected	< 10.0.28000.2525

Microsoft

Windows Server 2012

affected

Version	Status	Constraints
`6.2.9200.0`	affected	< 6.2.9200.26226

Microsoft

Windows Server 2012 (Server Core installation)

affected

Version	Status	Constraints
`6.2.9200.0`	affected	< 6.2.9200.26226

Microsoft

Windows Server 2012 R2

affected

Version	Status	Constraints
`6.3.9600.0`	affected	< 6.3.9600.23291

Microsoft

Windows Server 2012 R2 (Server Core installation)

affected

Version	Status	Constraints
`6.3.9600.0`	affected	< 6.3.9600.23291

Microsoft

Windows Server 2016

affected

Version	Status	Constraints
`10.0.14393.0`	affected	< 10.0.14393.9339

Microsoft

Windows Server 2016 (Server Core installation)

affected

Version	Status	Constraints
`10.0.14393.0`	affected	< 10.0.14393.9339

Microsoft

Windows Server 2019

affected

Version	Status	Constraints
`10.0.17763.0`	affected	< 10.0.17763.9020

Microsoft

Windows Server 2019 (Server Core installation)

affected

Version	Status	Constraints
`10.0.17763.0`	affected	< 10.0.17763.9020

Microsoft

Windows Server 2022

affected

Version	Status	Constraints
`10.0.20348.0`	affected	< 10.0.20348.5386

Microsoft

Windows Server 2025

affected

Version	Status	Constraints
`10.0.26100.0`	affected	< 10.0.26100.33158

Microsoft

Windows Server 2025 (Server Core installation)

affected

Version	Status	Constraints
`10.0.26100.0`	affected	< 10.0.26100.33158

Configuration 1 [-]

OR	cpe:2.3:o:microsoft:windows_10_1607:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1607:::::::x86:*
	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:::::::arm64:*
	cpe:2.3:o:microsoft:windows_10_21h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_21h2:::::::x86:*
	cpe:2.3:o:microsoft:windows_10_22h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_10_22h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_22h2:::::::x86:*
	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_2012:-:::::::*
	cpe:2.3:o:microsoft:windows_server_2012:r2:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:::::-::x64:
	cpe:2.3:o:microsoft:windows_server_2019:::::-::x64:
	cpe:2.3:o:microsoft:windows_server_2022:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2025:::::::x64:*

No data.

Vendor Product Versions

Microsoft

Windows 10 1607

Version	Status	Scheme	Platform
`[10.0.14393.0,10.0.14393.9339)`	affected	generic	['32-bit_systems', 'x64-based_systems']

Microsoft

Windows 10 1809

Version	Status	Scheme	Platform
`[10.0.17763.0,10.0.17763.9020)`	affected	generic	['32-bit_systems', 'x64-based_systems']

Microsoft

Windows 10 21h2

Version	Status	Scheme	Platform
`[10.0.19044.0,10.0.19044.7548)`	affected	generic	['32-bit_systems', 'arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 10 22h2

Version	Status	Scheme	Platform
`[10.0.19045.0,10.0.19045.7548)`	affected	generic	['32-bit_systems', 'arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 11 24h2

Version	Status	Scheme	Platform
`[10.0.26100.0,10.0.26100.8875)`	affected	generic	['arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 11 25h2

Version	Status	Scheme	Platform
`[10.0.26200.0,10.0.26100.8875)`	affected	generic	['arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 11 26h1

Version	Status	Scheme	Platform
`[10.0.28000.0,10.0.28000.2525)`	affected	generic	['arm64-based_systems', 'x64-based_systems']

Microsoft

Windows Server 2012

Version	Status	Scheme	Platform
`[6.2.9200.0,6.2.9200.26226)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2012 (server Core Installation)

Version	Status	Scheme	Platform
`[6.2.9200.0,6.2.9200.26226)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2012 R2

Version	Status	Scheme	Platform
`[6.3.9600.0,6.3.9600.23291)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2012 R2 (server Core Installation)

Version	Status	Scheme	Platform
`[6.3.9600.0,6.3.9600.23291)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2016

Version	Status	Scheme	Platform
`[10.0.14393.0,10.0.14393.9339)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2016 (server Core Installation)

Version	Status	Scheme	Platform
`[10.0.14393.0,10.0.14393.9339)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2019

Version	Status	Scheme	Platform
`[10.0.17763.0,10.0.17763.9020)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2019 (server Core Installation)

Version	Status	Scheme	Platform
`[10.0.17763.0,10.0.17763.9020)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2022

Version	Status	Scheme	Platform
`[10.0.20348.0,10.0.20348.5386)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2025

Version	Status	Scheme	Platform
`[10.0.26100.0,10.0.26100.33158)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2025 (server Core Installation)

Version	Status	Scheme	Platform
`[10.0.26100.0,10.0.26100.33158)`	affected	generic	['x64-based_systems']

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Apply the Microsoft security update for CVE‑2026‑58540 via Windows Update or the Microsoft Update Catalog.
Restrict execution of Microsoft Installer (msiexec.exe) for non‑administrator accounts, ensuring the Windows Installer service runs only under administrative privileges or denying install permissions to standard users.
Adopt Microsoft Security Baselines or harden local privilege management by limiting the number of local administrator accounts and enforcing least‑privilege policies to reduce the impact of potential privilege escalation.

Generated by OpenCVE AI on August 12, 2026 at 10:03 UTC.

Tracking

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.298% probability within 30 days)

Exploitation none

Automatable no

Technical Impact total

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58540

History

Aug 7, 2026 10:00 AM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Microsoft windows 10 21h2 Microsoft windows 10 22h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2012 (server Core Installation) Microsoft windows Server 2012 R2 Microsoft windows Server 2012 R2 (server Core Installation) Microsoft windows Server 2016 (server Core Installation) Microsoft windows Server 2019 (server Core Installation) Microsoft windows Server 2025 (server Core Installation)
Vendors & Products		Microsoft windows 10 21h2 Microsoft windows 10 22h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2012 (server Core Installation) Microsoft windows Server 2012 R2 Microsoft windows Server 2012 R2 (server Core Installation) Microsoft windows Server 2016 (server Core Installation) Microsoft windows Server 2019 (server Core Installation) Microsoft windows Server 2025 (server Core Installation)

Jul 14, 2026 6:30 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Jul 14, 2026 5:45 PM Description updated. Title updated. First appearance in the feed. Weaknesses updated. Affected versions updated. Affected vendors updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		Improper authorization in Windows Installer allows an authorized attacker to elevate privileges locally.
Title		Windows Installer Elevation of Privilege Vulnerability
First Time appeared		Microsoft Microsoft windows 10 1607 Microsoft windows 10 1809 Microsoft windows 10 21h2 Microsoft windows 10 22h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2012 Microsoft windows Server 2012 R2 Microsoft windows Server 2016 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
Weaknesses		CWE-285
CPEs		cpe:2.3:o:microsoft:windows_10_1607:::::::x86:* cpe:2.3:o:microsoft:windows_10_1809:::::::x86:* cpe:2.3:o:microsoft:windows_10_21H2:::::::x86:* cpe:2.3:o:microsoft:windows_10_22H2:::::::x64:* cpe:2.3:o:microsoft:windows_11_24H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_25H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_26H1:::::::x64:* cpe:2.3:o:microsoft:windows_server_2012:::::::x64:* cpe:2.3:o:microsoft:windows_server_2012_R2:::::::x64:* cpe:2.3:o:microsoft:windows_server_2016:::::::: cpe:2.3:o:microsoft:windows_server_2019:::::::: cpe:2.3:o:microsoft:windows_server_2022:::::::: cpe:2.3:o:microsoft:windows_server_2025::::::::
Vendors & Products		Microsoft Microsoft windows 10 1607 Microsoft windows 10 1809 Microsoft windows 10 21h2 Microsoft windows 10 22h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2012 Microsoft windows Server 2012 R2 Microsoft windows Server 2016 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58540
Metrics		cvssV3_1 `{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}`

Subscriptions

Microsoft Windows 10 1607 Windows 10 1809 Windows 10 21h2 Windows 10 21h2 Windows 10 22h2 Windows 10 22h2 Windows 11 24h2 Windows 11 24h2 Windows 11 25h2 Windows 11 25h2 Windows 11 26h1 Windows 11 26h1 Windows Server 2012 Windows Server 2012 (server Core Installation) Windows Server 2012 R2 Windows Server 2012 R2 Windows Server 2012 R2 (server Core Installation) Windows Server 2016 Windows Server 2016 (server Core Installation) Windows Server 2019 Windows Server 2019 (server Core Installation) Windows Server 2022 Windows Server 2025 Windows Server 2025 (server Core Installation)

Weaknesses