OTPulse

Windows SMB Information Disclosure Vulnerability

MonitorCVSS 5.5CVE-2026-50690Jul 14, 2026
Microsoft
IT in OT - Windows Server and Active Directory are widely deployed in OT environments
Attack path
Attack VectorLocal
Auth RequiredLow
ComplexityLow
User InteractionNone needed
Summary

An uninitialized resource vulnerability in Windows SMB allows an authorized local attacker to disclose sensitive information from memory. The vulnerability affects multiple versions of Windows 10, Windows 11, Windows Server 2016, 2019, 2022, and 2025. Microsoft has released fixes in the July 2026 security update across all affected product lines.

What this means
What could happen
An attacker with local access could read sensitive information from uninitialized memory in Windows SMB, potentially exposing credentials, configuration data, or other confidential information stored in RAM.
Who's at risk
Windows administrators running Windows 10 (versions 1607, 1809, 21H2, 22H2), Windows 11 (versions 24H2, 25H2, 26H1), Windows Server 2016, 2019, 2022, and 2025. This affects workstations and servers with SMB enabled across IT and engineering networks.
How it could be exploited
An attacker must have local logon access to the Windows system. Once logged in, they can trigger the uninitialized memory disclosure in SMB, allowing them to read data that should not be accessible.
Prerequisites
  • Local user account on the Windows system
  • Ability to initiate SMB operations on the local machine
Low attack complexityRequires local authenticationNo active exploitation reportedLow EPSS score
Exploitability
Unlikely to be exploited — EPSS score 0.4%
Affected products (23)
23 with fix
ProductAffected VersionsFix Status
Windows 10 Version 1809 for 32-bit SystemsAll versionsBuild 10.0.17763.9020
Windows 10 Version 1809 for x64-based SystemsAll versionsBuild 10.0.17763.9020
Windows Server 2019All versionsBuild 10.0.17763.9020
Windows Server 2019 (Server Core installation)All versionsBuild 10.0.17763.9020
Windows Server 2022All versionsBuild 10.0.20348.5386
Remediation & Mitigation
0/1
Schedule — requires maintenance window
0/1

Patching may require device reboot — plan for process interruption

HOTFIXApply Microsoft's July 2026 security update to all affected Windows systems
View full vendor advisory
API: /api/v1/advisories/471ae8d7-9b8d-4b1d-b12f-0b2b8af3e48e

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Windows SMB Information Disclosure Vulnerability | CVSS 5.5 - OTPulse