Is CVE-2021-31956 actively exploited?

Yes. CVE-2021-31956 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, which means exploitation in the wild has been confirmed.

Can CVE-2021-31956 be exploited remotely?

The attack vector of CVE-2021-31956 has not been classified yet.

What is the CVSS score of CVE-2021-31956?

CVE-2021-31956 has not received a CVSS score yet.

HOME VULNERABILITIESCVE-2021-31956

HIGHCISA KEVIN THE WILD

CVE-2021-31956

Published: November 3, 2021

EPSS:88.71%probability of exploitation in 30 daysPercentile:99.5th

Official Description

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

NVD Source

CISA KEV Advisory

Microsoft Windows NTFS Privilege Escalation Vulnerability

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

Added to KEV: 2021-11-03Federal patch deadline: 2021-11-17

Required Action (CISA)

Apply updates per vendor instructions.

Risk Analysis

An unspecified vulnerability in Microsoft Windows New Technology File System (NTFS) allows attackers to escalate privileges through a specially crafted application. This high-severity flaw, with an EPSS score of 0.88708 and confirmed exploitation in the wild, poses a significant risk to system security once an attacker has initial access.

This vulnerability has been actively exploited in the wild and is listed in CISA's KEV catalog. Exploitation requires an attacker to run a specially crafted application on the target system, indicating local privilege escalation.

Recommended Action

Apply all available security updates and patches for Microsoft Windows. Implement principle of least privilege for user accounts and ensure endpoint detection and response (EDR) solutions are up-to-date.

Generated by the CTIWATCH analysis pipeline from this CVE's metadata (CVSS, EPSS, KEV status, exploit intelligence). Verify against vendor advisories before acting.

Technical Analysis

CVE-2021-31956 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

CISA has added CVE-2021-31956 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.