CVE-2021-31956

Exploited in the Wild ✓ Confirmed 0-Day ★ Google Project Zero
Triaged: March 5, 2026 4 articles Published: 2021-06-08

EPSS Score

Source: FIRST.org · 2026-05-24
90.72%
probability
This CVE has a 90.72% probability of being exploited in the next 30 days.
0% Top 99.6th percentile of all CVEs 100%

CVSS v3.1

Source: VulnerabilityLookup (CIRCL)
7.8
HIGH
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Temporal
Exploit Code Maturity
Functional
Remediation Level
Official Fix
Report Confidence
Confirmed
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

Description

Project Zero
Heap-based buffer overflow in ntfs.sys

Affected Products

Microsoft
Windows 10 Version 1809
10.0.0
Microsoft
Windows Server 2019
10.0.0
Microsoft
Windows Server 2019 (Server Core installation)
10.0.0
Microsoft
Windows 10 Version 1909
10.0.0
Microsoft
Windows 10 Version 21H1
10.0.0

Attack Intelligence

Google Project Zero

Discovered
April 14, 2021
Patched
June 8, 2021
Reported by
Boris Larin (Oct0xor) of Kaspersky Lab
Root Cause Analysis
???

Exploits & PoC

hzshang/CVE-2021-31956

PoC CVE-2021-31956 — hzshang/CVE-2021-31956

0
deletehead/Pool-Overflow-CVE-2021-31956

Kernel Pool Overflow Exploit targeting CVE-2021-31956

0
2 repos — triés par ⭐ Rechercher sur GitHub ↗

Signal Intelligence

Confidence
95%
EPSS 90.72%
CVSS v3.1 7.8
Mentions 4
Last Seen Nov 09, 2021

CNA Information

CNA Assigner
microsoft
CNA Title
Windows NTFS Elevation of Privilege Vulnerability

Analyst Note

Auto-imported from Google Project Zero — confirmed zero-day by definition.

Triage Info

Decided atMar 05, 2026
Published DateJun 08, 2021