CVE-2021-31956: Windows NTFS Elevation of Privilege Vulnerability

Overview

Severity
High (CVSS 7.8)
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
Category
Elevation of Privilege
Exploit Status
Actively Exploited
Exploitation Likelihood
Detected
Patch Tuesday
2021-Jun
Released
2021-06-08
EPSS Score
90.72% (percentile: 99.6%)
CISA KEV
Listed — due 2021-11-17

FAQ

How could an attacker exploit this vulnerability? To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and take control of an affected system. Additionally, an attacker could convince a local user to open a malicious file. The attacker would have to convince the user to click a link, typically by way of an enticement in an email or instant message, and then convince them to open the specially crafted file.

Detection & Weaponization (1 sources)

Maturity: Exploit

  • GitHub PoC: 4 repositories

Affected Products (39)

Windows

  • Windows 10 Version 1809 for 32-bit Systems
  • Windows 10 Version 1809 for x64-based Systems
  • Windows 10 Version 1809 for ARM64-based Systems
  • Windows Server 2019
  • Windows Server 2019 (Server Core installation)
  • Windows 10 Version 1909 for 32-bit Systems
  • Windows 10 Version 1909 for x64-based Systems
  • Windows 10 Version 1909 for ARM64-based Systems
  • Windows 10 Version 21H1 for x64-based Systems
  • Windows 10 Version 21H1 for ARM64-based Systems
  • Windows 10 Version 21H1 for 32-bit Systems
  • Windows 10 Version 2004 for 32-bit Systems
  • Windows 10 Version 2004 for ARM64-based Systems
  • Windows 10 Version 2004 for x64-based Systems
  • Windows Server, version 2004 (Server Core installation)
  • Windows 10 Version 20H2 for 32-bit Systems
  • Windows 10 Version 20H2 for ARM64-based Systems
  • Windows Server, version 20H2 (Server Core Installation)
  • Windows 10 for 32-bit Systems
  • Windows 10 for x64-based Systems
  • Windows 10 Version 1607 for 32-bit Systems
  • Windows 10 Version 1607 for x64-based Systems
  • Windows Server 2016
  • Windows Server 2016 (Server Core installation)
  • Windows 8.1 for 32-bit systems
  • Windows 8.1 for x64-based systems
  • Windows RT 8.1

ESU

  • Windows 7 for 32-bit Systems Service Pack 1
  • Windows 7 for x64-based Systems Service Pack 1
  • 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 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 2012
  • Windows Server 2012 (Server Core installation)
  • Windows Server 2012 R2
  • Windows Server 2012 R2 (Server Core installation)

Security Updates (13)

Acknowledgments

Boris Larin (<a href="https://twitter.com/oct0xor">oct0xor</a>) of <a href="https://www.kaspersky.com/">Kaspersky Lab</a>

Revision History

  • 2021-06-08: Information published.