CVE-2025-55234HighCVSS 8.8

Windows SMB Elevation of Privilege Vulnerability

Published
June 3, 2026
Last Modified
—

🔗 CVE IDs covered (1)

CVE-2025-55234 →

📋 Description

SMB Server might be susceptible to relay attacks depending on the configuration. An attacker who successfully exploited these vulnerabilities could perform relay attacks and make the users subject to elevation of privilege attacks. The SMB Server already supports mechanisms for hardening against relay attacks: SMB Server signing SMB Server Extended Protection for Authentication (EPA) Microsoft is releasing this CVE to provide customers with audit capabilities to help them to assess their environment and to identify any potential device or software incompatibility issues before deploying SMB Server hardening measures that protect against relay attacks. If you have not already enabled SMB Server hardening measures, we advise customers to take the following actions to be protected from these relay attacks: Assess your environment by utilizing the audit capabilities that we are exposing in the September 2025 security updates. See Support for Audit Events to deploy SMB Server Hardening—SMB Server Signing & SMB Server EPA. Adopt appropriate SMB Server hardening measures.

🎯 Affected products37

  • Windows 10 Version 1607 for 32-bit Systems
  • Windows 10 Version 1607 for x64-based Systems
  • Windows 10 Version 1809 for 32-bit Systems
  • Windows 10 Version 1809 for x64-based Systems
  • Windows 10 Version 21H2 for 32-bit Systems
  • Windows 10 Version 21H2 for ARM64-based Systems
  • Windows 10 Version 21H2 for x64-based Systems
  • Windows 10 Version 22H2 for 32-bit Systems
  • Windows 10 Version 22H2 for ARM64-based Systems
  • Windows 10 Version 22H2 for x64-based Systems
  • Windows 10 for 32-bit Systems
  • Windows 10 for x64-based Systems
  • Windows 11 Version 22H2 for ARM64-based Systems
  • Windows 11 Version 22H2 for x64-based Systems
  • Windows 11 Version 23H2 for ARM64-based Systems
  • Windows 11 Version 23H2 for x64-based Systems
  • Windows 11 Version 24H2 for ARM64-based Systems
  • Windows 11 Version 24H2 for x64-based Systems
  • Windows Server 2008 R2 for x64-based Systems Service Pack 1
  • Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)
  • Windows Server 2008 for 32-bit Systems Service Pack 2
  • Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)
  • Windows Server 2008 for x64-based Systems Service Pack 2
  • Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)
  • Windows Server 2012
  • Windows Server 2012 (Server Core installation)
  • Windows Server 2012 R2
  • Windows Server 2012 R2 (Server Core installation)
  • Windows Server 2016
  • Windows Server 2016 (Server Core installation)
  • +7 more not shown

✅ Remediation

KB5065428 (Security Update) — fixed build 10.0.17763.7792 KB5065432 (Security Update) — fixed build 10.0.20348.4171 KB5065306 (Security Hotpatch Update) — fixed build 10.0.20348.4106 KB5065429 (Security Update) — fixed build 10.0.19044.6332 KB5065431 (Security Update) — fixed build 10.0.22621.5909 KB5065429 (Security Update) — fixed build 10.0.19045.6332 KB5065426 (Security Update) — fixed build 10.0.26100.6584 KB5065474 (SecurityHotpatchUpdate) — fixed build 10.0.26100.6508 KB5065431 (Security Update) — fixed build 10.0.22631.5909 KB5065425 (Security Update) — fixed build 10.0.25398.1849 KB5065474 (Security Hotpatch Update) — fixed build 10.0.26100.6508 KB5065430 (Security Update) — fixed build 10.0.10240.21128 KB5065427 (Security Update) — fixed build 10.0.14393.8422 KB5065508 (Monthly Rollup) — fixed build 6.0.6003.23529 KB5065511 (Security Only) — fixed build 6.0.6003.23529 KB5065468 (Monthly Rollup) — fixed build 6.1.7601.27929 KB5065510 (Security Only) — fixed build 6.1.7601.27929 KB5065509 (Monthly Rollup) — fixed build 6.2.9200.25675 KB5065507 (Monthly Rollup) — fixed build 6.3.9600.22774

🔗 References (33)