CVE-2021-31977HighCVSS 8.6

Windows Hyper-V Denial of Service Vulnerability

Published
June 8, 2021
Last Modified
—

🔗 CVE IDs covered (1)

CVE-2021-31977 →

📋 Description

How might an attacker attempt to exploit this vulnerability? By sending a specially crafted message to the Hyper-V host virtualization stack, a guest VM could cause a reference count in the host virtualization stack to be leaked. In most circumstances, this would result in a memory leak on the Hyper-V host. If the leaked reference count value were to overflow, reference count hardening built-in to the Hyper-V virtualization stack would cause the host to bugcheck (crash) in a controlled manner, mitigating this issue against exploitation for code execution or privilege elevation.

🎯 Affected products12

  • Windows 10 Version 1607 for x64-based Systems
  • Windows 10 Version 1809 for x64-based Systems
  • Windows 10 Version 1909 for x64-based Systems
  • Windows 10 Version 2004 for x64-based Systems
  • Windows 10 Version 21H1 for x64-based Systems
  • Windows 10 for x64-based Systems
  • Windows Server 2016
  • Windows Server 2016 (Server Core installation)
  • Windows Server 2019
  • Windows Server 2019 (Server Core installation)
  • Windows Server, version 2004 (Server Core installation)
  • Windows Server, version 20H2 (Server Core Installation)

✅ Remediation

KB5003646 (Security Update) — fixed build 10.0.17763.1999 KB5003635 (Security Update) — fixed build 10.0.18363.1621 KB5003637 (Security Update) — fixed build 10.0.19043.1052 KB5003637 (Security Update) — fixed build 10.0.19041.1052 KB5003637 (Security Update) — fixed build 10.0.19042.1052 KB5003687 (Security Update) — fixed build 10.0.10240.18967 KB5003638 (Security Update) — fixed build 10.0.14393.4467

🔗 References (9)