CVE-2024-26234: Windows 10 1507 Auth Bypass Vulnerability

CVE-2024-26234 Overview

CVE-2024-26234 is a Proxy Driver Spoofing Vulnerability affecting multiple versions of Microsoft Windows and Windows Server. Microsoft disclosed the issue on April 9, 2024 as part of the monthly security update cycle. The flaw is categorized under [CWE-284] Improper Access Control and enables a local attacker holding high privileges to spoof a signed proxy driver. Successful exploitation impacts confidentiality, integrity, and availability on the affected host. The vulnerability requires local access and no user interaction, which limits remote exposure but raises concern for post-compromise persistence scenarios.

Critical Impact
A local attacker with high privileges can leverage a spoofed, validly signed proxy driver to subvert trust controls on Windows and Windows Server systems.

Affected Products

Microsoft Windows 10 (1507, 1607, 1809, 21H2, 22H2)
Microsoft Windows 11 (21H2, 22H2, 23H2)
Microsoft Windows Server 2008, 2012, 2016, 2019, 2022, and 2022 23H2

Discovery Timeline

2024-04-09 - CVE-2024-26234 published to NVD
2024-04-09 - Microsoft releases security update for CVE-2024-26234
2025-01-08 - Last updated in NVD database

Technical Details for CVE-2024-26234

Vulnerability Analysis

The vulnerability stems from improper access control in how Windows validates a proxy driver component. An attacker who already holds high privileges on the system can introduce a driver that appears legitimately signed and trusted. Because the proxy driver passes signature checks, defensive tooling that relies on signature-based trust may treat the spoofed component as benign. This creates a path for adversaries to establish kernel-level footholds while masquerading as a trusted publisher.

The issue has been associated publicly with reporting on signed driver abuse in malware campaigns. Once loaded, the spoofed driver can be used to operate at the kernel boundary, observe sensitive operations, and tamper with userland or kernel state.

Root Cause

The root cause is improper access control [CWE-284] within the signing and validation chain for proxy driver components. Trust attribution does not adequately bind the signed component to its intended origin, allowing a high-privileged local actor to substitute a controlled driver that retains valid signature attributes.

Attack Vector

Exploitation requires local access with high privileges and does not require user interaction. The CVSS vector indicates an attack scope limited to the compromised host with high impact on confidentiality, integrity, and availability. In practice, this vulnerability is most relevant during post-exploitation, where attackers seek to load kernel components without triggering driver-trust controls.

No public proof-of-concept exploit is associated with this CVE in NVD references, and the vulnerability is not currently listed in the CISA Known Exploited Vulnerabilities catalog. The EPSS score places it in the upper percentile for exploitation likelihood relative to all scored CVEs, reflecting the broader interest in signed driver abuse techniques.

No verified exploitation code is published with this advisory. See the Microsoft Security Update CVE-2024-26234 advisory for vendor-supplied technical details.

Detection Methods for CVE-2024-26234

Indicators of Compromise

Unexpected kernel driver load events referencing publishers not part of the organization's approved signing list.
Newly created services pointing to driver binaries dropped in user-writable or non-standard paths such as %TEMP% or %PROGRAMDATA%.
Driver files whose certificate metadata, version information, or product name appears inconsistent with the claimed publisher.

Detection Strategies

Audit Windows kernel driver load events (Sysmon Event ID 6) and compare loaded drivers against an allowlist of approved publishers and hashes.
Correlate services.exe activity that creates kernel-mode services with subsequent ntoskrnl driver load events to detect privileged driver installation chains.
Inspect driver certificate chains for spoofed Common Name fields, cross-signed certificates known to be abused, or revoked certificate usage.

Monitoring Recommendations

Forward Sysmon, Windows Security, and CodeIntegrity operational logs to a centralized SIEM for retention and correlation.
Alert on first-seen drivers across the fleet, prioritizing systems where the driver appears on a single host within a short window.
Track changes to HKLM\SYSTEM\CurrentControlSet\Services keys that register kernel-mode services with Type value 0x1.

How to Mitigate CVE-2024-26234

Immediate Actions Required

Apply the April 2024 Microsoft security updates to all affected Windows client and Windows Server systems referenced in the advisory.
Inventory existing kernel-mode drivers across the fleet and validate signing chains against the organization's approved publisher list.
Restrict local administrative privileges to reduce the population of accounts that can install kernel-mode drivers.

Patch Information

Microsoft published patches for CVE-2024-26234 through the standard Windows Update channel. Refer to the Microsoft Security Update CVE-2024-26234 advisory for the specific KB articles aligned to each affected Windows and Windows Server version.

Workarounds

Enable Microsoft's recommended driver block list and Hypervisor-protected Code Integrity (HVCI) on systems that support it.
Enforce Windows Defender Application Control (WDAC) policies that allowlist drivers by publisher and file hash.
Limit interactive logon and administrative access on servers and privileged workstations to constrain who can introduce drivers.

bash

# Configuration example
# Enable the Microsoft vulnerable driver blocklist (Windows 11 / Server 2022+)
DISM /Online /Enable-Feature /FeatureName:HypervisorPlatform /All
# Apply a WDAC policy enforcing allowlisted driver publishers
CiTool.exe --update-policy C:\Policies\WDAC_DriverAllowlist.cip