PT-2021-3303 · Microsoft · Windows Ntfs+1

Published 2021-06-08 · Updated 2026-06-15 · CVE-2021-31956

Positive Technologies (AI Summary)

CVSS v2.0

9.3

High

Base vector

AV:N/AC:M/Au:N/C:C/I:C/A:C

Name of the Vulnerable Software and Affected Versions Windows NTFS (affected versions not specified)

Description An elevation of privilege issue exists in the ntfs.sys driver due to improper access control. The flaw involves a heap overflow—a condition where data exceeds the allocated memory buffer on the heap—which allows the corruption of adjacent kernel objects. By manipulating the kernel heap, an attacker can create an arbitrary read/write primitive to steal a SYSTEM token from another process, thereby gaining elevated privileges on the system.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

DoS

LPE

Buffer Overflow

Integer Underflow

Weakness Enumeration

CWE-119

CWE-264

CWE-191

Related Identifiers

BDU:2021-03077

CVE-2021-31956

Affected Products

Windows

Windows Ntfs

References · 33

• 🔥 https://github.com/aazhuliang/CVE-2021-31956-EXP · Exploit
• 🔥 https://github.com/Y3A/CVE-2021-31956 · Exploit
• https://osv.dev/vulnerability/CVE-2021-31956 · Vendor Advisory
• https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2021-31956 · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-31956 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2021-31956 · Security Note
• https://bdu.fstec.ru/vul/2021-03077 · Security Note
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31956 · Vendor Advisory
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-31956 · Vendor Advisory
• https://github.com/3sjay/sploits · Note
• https://t.me/cvenotify/87771 · Telegram Post
• https://cisa.gov/known-exploited-vulnerabilities-catalog · Note
• https://t.me/cybersecuritytechnologies/4110 · Telegram Post
• https://t.me/cveNotify/141040 · Telegram Post
• https://twitter.com/ShaiiikShoaiiib/status/1839510706133008585 · Twitter Post