Privilege escalation in Microsoft Windows NTFS

1) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU53891

Risk: Medium

CVSSv4.0: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Green]

CVE-ID: CVE-2021-31956

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: Yes

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists within the NTFS subsystem in Microsoft Windows. A local user can run a specially crafted program to execute arbitrary code with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Windows: 7 - 10

Windows Server: 2008 R2 - 2019 2004

CPE2.3

• cpe:2.3:o:microsoft:windows:*:*:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:8.1:*:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_20H2:10.0.19042.572:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_21H1:10.0.19043.985:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_1607:10.0.14393.10:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_1809:10.0.17763.1:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_1909:10.0.18363.476:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_2004:10.0.19041.264:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_server:*:*:*:*:*:*:*:*

External links

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31956

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.