CVE-2026-50475 Overview
CVE-2026-50475 is a buffer over-read vulnerability in the Windows Kernel. An authenticated local attacker can read memory beyond the intended buffer boundary and disclose sensitive kernel information. The weakness is categorized under [CWE-126] (Buffer Over-read).
Microsoft documented the issue in the Microsoft CVE-2026-50475 Advisory. Cisco Talos published additional technical context in the Talos Intelligence Vulnerability Report TALOS-2026-2443.
Critical Impact
A local, authorized attacker can read out-of-bounds kernel memory, exposing data that may include pointers, cryptographic material, or other sensitive information useful for further exploitation.
Affected Products
- Microsoft Windows (Windows Kernel component) — refer to the Microsoft advisory for the specific builds addressed
Discovery Timeline
- 2026-07-14 - CVE-2026-50475 published to the National Vulnerability Database
- 2026-07-16 - Last updated in NVD database
Technical Details for CVE-2026-50475
Vulnerability Analysis
The flaw is a buffer over-read inside the Windows Kernel. The kernel reads past the end of an allocated buffer while processing input from an authenticated local caller. The extra bytes returned to the caller can contain adjacent kernel data.
Because the attack surface is local and requires valid credentials, exploitation is limited to users or processes that already hold a session on the target host. The vulnerability does not modify data or affect availability. Its value to an attacker lies in information disclosure, particularly bypassing Kernel Address Space Layout Randomization (KASLR) or leaking secrets that support privilege escalation chains. The EPSS score of 0.49% reflects a low near-term probability of widespread exploitation.
Root Cause
The root cause is missing or incorrect length validation on a kernel read operation. When the kernel copies data from an internal structure toward a user-controlled destination, it uses a size that exceeds the source buffer. This condition matches [CWE-126], where the read index moves past the end of the allocated region.
Attack Vector
Exploitation requires local access and low-privilege authentication. An attacker invokes the vulnerable kernel code path — typically through a system call or IOCTL — with crafted parameters that trigger the over-read. The kernel returns memory contents that were not intended for the caller. No user interaction is required and the scope remains unchanged.
No public proof-of-concept exploit is currently listed for this CVE. Technical specifics are described in the vendor and Talos references.
Detection Methods for CVE-2026-50475
Indicators of Compromise
- No public indicators of compromise have been published for CVE-2026-50475 at this time.
- Unexpected invocations of kernel interfaces by low-privilege user processes may warrant review.
Detection Strategies
- Monitor for local processes issuing unusual volumes of system calls or IOCTLs against kernel components referenced in the Microsoft advisory.
- Correlate information-disclosure attempts with subsequent privilege-escalation activity on the same host.
- Track patch state across the fleet and flag endpoints still running vulnerable Windows builds.
Monitoring Recommendations
- Enable Windows kernel and Sysmon telemetry for process creation, driver load, and handle activity, and forward events to a central analytics platform.
- Alert on non-administrative processes that repeatedly probe kernel interfaces or crash kernel-mode components.
- Review endpoint detection and response (EDR) alerts for local privilege-escalation patterns that often follow kernel information leaks.
How to Mitigate CVE-2026-50475
Immediate Actions Required
- Apply the Microsoft security update referenced in the Microsoft CVE-2026-50475 Advisory as soon as testing permits.
- Prioritize patching on multi-user systems, jump hosts, and endpoints accessible to low-trust accounts.
- Audit local account inventories and remove unnecessary interactive logon rights.
Patch Information
Microsoft has issued an official fix through the Microsoft Security Response Center. Consult the vendor advisory for the exact Knowledge Base article, build numbers, and superseding updates that apply to each Windows version in your environment.
Workarounds
- No vendor-supplied workaround is documented; installing the security update is the supported remediation.
- Reduce exposure by restricting local logon and limiting the number of accounts that can execute untrusted binaries on production systems.
- Enforce application control policies such as Windows Defender Application Control to block unauthorized code from reaching the vulnerable kernel path.
# Verify installed Windows updates and current build
wmic qfe list brief /format:table
[System.Environment]::OSVersion.Version
# Trigger Windows Update scan and install (run elevated)
UsoClient StartScan
UsoClient StartInstall
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
