Known exploited vulnerability

CVE-2021-31956

Microsoft Windows NTFS Privilege Escalation Vulnerability

What is affected

Vendor Microsoft
Product Windows
Weakness CWE-191, CWE-787

The vulnerability

Microsoft Windows New Technology File System (NTFS) contains an unspecified vulnerability that allows attackers to escalate privileges via a specially crafted application.

Required action

Apply updates per vendor instructions.

US federal civilian agencies were required to act by 17 November 2021 under BOD 22-01. The deadline is a compliance date, not a measure of severity — it says nothing about how dangerous the flaw is to anyone else.

Where this comes from

Every field on this page is taken from the CISA Known Exploited Vulnerabilities catalog, last synced 13 Nov 2026, 00:30. Nothing here is our own assessment. For the technical scoring, see the NVD record below.

NVD record ↗ CVE.org record ↗

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