CVE-2020-0841: Windows Hard Link Elevation of Privilege Vulnerability

Overview

Severity

High (CVSS 7.8)

CVSS Vector

CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C

Category

Elevation of Privilege

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2020-Mar

Released

2020-03-10

EPSS Score

0.40% (percentile: 60.5%)

Description

An elevation of privilege vulnerability exists when Windows improperly handles hard links. An attacker who successfully exploited this vulnerability could overwrite a targeted file leading to an elevated status. 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. The security update addresses the vulnerability by correcting how Windows handles hard links.

Affected Products (26)

Windows

• Windows 10 Version 1803 for 32-bit Systems
• Windows 10 Version 1803 for x64-based Systems
• Windows Server, version 1803 (Server Core Installation)
• Windows 10 Version 1803 for ARM64-based Systems
• 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 Server, version 1909 (Server Core installation)
• Windows 10 Version 1709 for 32-bit Systems
• Windows 10 Version 1709 for x64-based Systems
• Windows 10 Version 1709 for ARM64-based Systems
• Windows 10 Version 1903 for 32-bit Systems
• Windows 10 Version 1903 for x64-based Systems
• Windows 10 Version 1903 for ARM64-based Systems
• Windows Server, version 1903 (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)

Security Updates (6)

• 4540689
• 4538461
• 4540673
• 4540681
• 4540693
• 4540670

Acknowledgments

JeongOh Kyea(@kkokkokye) of THEORI working with <a href="https://www.zerodayinitiative.com/">Trend Micro's Zero Day Initiative</a>, Zhiniang Peng (<a href="https://twitter.com/edwardzpeng">@edwardzpeng</a>) of Qihoo 360 Core security & Jiadong Lu

Revision History

• 2020-03-10: Information published.