CVE-2026-50442: Windows File Explorer Info Disclosure

CVE-2026-50442 Overview

CVE-2026-50442 is an information disclosure vulnerability in Windows File Explorer. An authorized local attacker can exploit the flaw to obtain sensitive information that should remain protected. The issue is classified under [CWE-200] (Exposure of Sensitive Information to an Unauthorized Actor).

Exploitation requires local access and low privileges but no user interaction. The vulnerability affects confidentiality only, with no impact on integrity or availability. Microsoft published the advisory on July 14, 2026.

Critical Impact
An authenticated local user can retrieve sensitive information handled by Windows File Explorer, potentially aiding follow-on privilege escalation or lateral movement.

Affected Products

Microsoft Windows (File Explorer component)
Refer to the Microsoft CVE-2026-50442 Advisory for the current list of affected builds
Consult Microsoft update catalogs for supported Windows client and server versions

Discovery Timeline

2026-07-14 - CVE-2026-50442 published to NVD
2026-07-15 - Last updated in NVD database

Technical Details for CVE-2026-50442

Vulnerability Analysis

The vulnerability resides in Windows File Explorer (explorer.exe) and results in the exposure of sensitive information to an unauthorized actor. An attacker with local access and standard user privileges can trigger conditions that cause File Explorer to reveal data that should be restricted by access controls.

Because the attack vector is local and requires authentication, exploitation depends on the attacker already having an interactive session or a foothold on the target host. The confidentiality impact is high, while integrity and availability remain unaffected.

An EPSS score of 0.362% indicates a low current probability of exploitation activity, but information disclosure flaws are frequently chained with other vulnerabilities. Exposed data can include file metadata, path information, or content that assists an attacker in mapping the environment.

Root Cause

The root cause is categorized under [CWE-200], indicating that File Explorer discloses sensitive information to an actor that is not explicitly authorized to receive it. Microsoft has not released detailed technical internals. Refer to the Microsoft CVE-2026-50442 Advisory for authoritative technical details.

Attack Vector

An attacker must be authenticated on the target Windows system with at least low-level privileges. No user interaction from another user is required. The attacker interacts with File Explorer functionality locally to trigger disclosure of protected information. Remote exploitation is not possible with this vulnerability class.

No public proof-of-concept exploit is available at the time of publication, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2026-50442

Indicators of Compromise

No specific indicators of compromise have been published by Microsoft for this vulnerability
Unexpected explorer.exe child processes spawned under standard user contexts accessing sensitive directories
Anomalous file enumeration patterns from non-administrative accounts targeting protected paths

Detection Strategies

Monitor process telemetry for explorer.exe activity that reads from directories outside the user's normal profile scope
Enable Windows auditing for object access (Event ID 4663) on sensitive file paths and review anomalies
Correlate local logon events (Event ID 4624 type 2) with subsequent file access patterns to identify reconnaissance behavior

Monitoring Recommendations

Ingest Windows Security and Sysmon logs into a centralized SIEM for behavioral analysis
Baseline normal File Explorer usage per user and alert on deviations involving protected content
Track patch compliance across the Windows fleet to confirm remediation coverage for CVE-2026-50442

How to Mitigate CVE-2026-50442

Immediate Actions Required

Apply the Microsoft security update referenced in the Microsoft CVE-2026-50442 Advisory as soon as it is available for your Windows build
Inventory affected Windows systems and prioritize patching on multi-user hosts and jump boxes
Review local user account privileges and remove unnecessary standard user access to shared systems

Patch Information

Microsoft has published the official advisory at Microsoft CVE-2026-50442 Advisory. Administrators should reference the advisory to identify the specific KB article and cumulative update applicable to each supported Windows version, then deploy through Windows Update, WSUS, Microsoft Intune, or Configuration Manager.

Workarounds

No official workaround has been published by Microsoft; applying the vendor patch is the recommended remediation
Restrict interactive local logon rights on sensitive systems to reduce the pool of potential attackers
Apply least-privilege access controls on sensitive directories to minimize information exposed if exploitation occurs

bash

# Verify Windows patch status via PowerShell
Get-HotFix | Sort-Object -Property InstalledOn -Descending | Select-Object -First 20

# Query current OS build to compare against Microsoft advisory
[System.Environment]::OSVersion.Version
(Get-ItemProperty 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion').DisplayVersion