CVE-2026-42976

Analyzed Analyzed - Analysis Complete

Missing Authentication in Windows RPC API Leads to Privilege Escalation

Publication date: 2026-08-11

Last updated on: 2026-08-16

Assigner: Microsoft Corporation

Description

Missing authentication for critical function in Windows RPC API allows an authorized attacker to elevate privileges locally.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-08-11

Last Modified

2026-08-16

Generated

2026-09-01

AI Q&A

2026-08-12

EPSS Evaluated

2026-08-30

NVD

CVE-2026-42976

EUVD

EUVD-2026-56604

Affected Vendors & Products

Vendor	Product	Version / Range
microsoft	windows_server_2012	r2
microsoft	windows_server_2012	*
microsoft	windows_10_1607	to 10.0.14393.9418 (exc)
microsoft	windows_10_1607	to 10.0.14393.9418 (exc)
microsoft	windows_10_1809	to 10.0.17763.9115 (exc)
microsoft	windows_10_1809	to 10.0.17763.9115 (exc)
microsoft	windows_10_21h2	to 10.0.19044.7663 (exc)
microsoft	windows_10_21h2	to 10.0.19044.7663 (exc)
microsoft	windows_10_21h2	to 10.0.19044.7663 (exc)
microsoft	windows_10_22h2	to 10.0.19045.7663 (exc)
microsoft	windows_10_22h2	to 10.0.19045.7663 (exc)
microsoft	windows_10_22h2	to 10.0.19045.7663 (exc)
microsoft	windows_11_24h2	to 10.0.26100.9106 (exc)
microsoft	windows_11_24h2	to 10.0.26100.9106 (exc)
microsoft	windows_11_26h1	to 10.0.28000.2704 (exc)
microsoft	windows_11_26h1	to 10.0.28000.2704 (exc)
microsoft	windows_11_25h2	to 10.0.26200.9106 (exc)
microsoft	windows_11_25h2	to 10.0.26200.9106 (exc)
microsoft	windows_server_2016	to 10.0.14393.9418 (exc)
microsoft	windows_server_2019	to 10.0.17763.9115 (exc)
microsoft	windows_server_2022	to 10.0.20348.5440 (exc)
microsoft	windows_server_2025	to 10.0.26100.33222 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-306	The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

Attack-Flow Graph

Executive Summary

This vulnerability is a missing authentication issue in the Windows RPC API. It allows an authorized attacker to escalate their privileges on a local system by exploiting a critical function that should require authentication.

Detection Guidance

This vulnerability involves missing authentication in Windows RPC API leading to local privilege escalation. Detection requires checking for unauthorized privilege changes or suspicious RPC API calls. Use Windows Event Viewer to review security logs for unusual privilege escalation events. Check for unpatched Windows systems using commands like 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' and verify installed updates with 'wmic qfe list'.

Impact Analysis

An attacker with local access could exploit this to gain higher privileges, potentially allowing them to install programs, view or delete data, or create new accounts with full user rights.

Compliance Impact

This vulnerability allows local privilege escalation due to missing authentication in Windows RPC API. While not directly impacting GDPR or HIPAA compliance, such vulnerabilities could enable unauthorized access to sensitive data, potentially violating these regulations if exploited.

Mitigation Strategies

Apply the latest security updates from Microsoft to address the missing authentication in the Windows RPC API. Monitor Microsoft's update guide for patches and install them promptly.

Hi! I’m here to help you understand CVE-2026-42976. Ask me anything about the vulnerability, its impact, or mitigation strategies.

0/70