Important CVSS 4.2 2018-09 archive

Executive Summary

A security feature bypass vulnerability exists when Windows Hyper-V BIOS loader fails to provide a high-entropy source. To exploit this vulnerability, an attacker would need to reboot a guest virtual machine numerous times until the vulnerability is triggered. The security update addresses the vulnerability by correcting security feature behavior to ensure Windows Hyper-V BIOS loader provides a high-entropy source.

Overview

4.2
CVSS MEDIUM
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
Category Security Feature Bypass
Released Sep 11 2018
Last Updated Sep 11 2018
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known

CVSS Vector

ATTACK VECTOR
Adjacent
ATTACK COMPLEXITY
High
PRIVILEGES REQUIRED
High
USER INTERACTION
None
SCOPE
Unchanged
CONFIDENTIALITY
None
INTEGRITY
High
AVAILABILITY
None
EXPLOIT CODE MATURITY
Proof-of-Concept
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 3.8

EPSS Score

No EPSS score available for this CVE.

View on FIRST.org

Affected Products

9 affected products
Product KB Article Severity Impact Restart Required
Windows 10 for x64-based Systems 4457132 (Security Update) Important Security Feature Bypass Yes
Windows 10 Version 1607 for x64-based Systems 4457131 (Security Update) Important Security Feature Bypass Yes
Windows 10 Version 1703 for x64-based Systems 4457138 (Security Update) Important Security Feature Bypass Yes
Windows 10 Version 1709 for x64-based Systems 4457142 (Security Update) Important Security Feature Bypass Yes
Windows 10 Version 1803 for x64-based Systems 4457128 (Security Update) Important Security Feature Bypass Yes
Windows Server 2016 4457131 (Security Update) Important Security Feature Bypass Yes
Windows Server 2016 (Server Core installation) 4457131 (Security Update) Important Security Feature Bypass Yes
Windows Server, version 1709 (Server Core Installation) 4457142 (Security Update) Important Security Feature Bypass Yes
Windows Server, version 1803 (Server Core Installation) 4457128 (Security Update) Important Security Feature Bypass Yes

Patches

5 patches
Article Type Restart
4457132 Security Update Yes
4457131 Security Update Yes
4457138 Security Update Yes
4457142 Security Update Yes
4457128 Security Update Yes

Known Exploits

Acknowledgments

Niels Ferguson of Microsoft Corporation