CVE-2021-40449

Microsoft Windows: Win32k Privilege Escalation

As of , CVE-2021-40449 in Microsoft Windows is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.

Exploited
Yes: CISA listed it on 17 November 2021
US federal deadline
1 December 202114 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Known
EPSS score
0.74Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
Not availableCISA listed it before 4 February 2022, where the EPSS files we read begin.
Public exploit
1 Metasploit module
Fix
No vendor link in CISA's entry

What CISA says to do

Apply updates per vendor instructions.

CISA's required action

What the flaw is

Unspecified vulnerability allows for an authenticated user to escalate privileges.

CISA's description

Win32k Elevation of Privilege Vulnerability

The CVE record's description, from microsoft

CVE published
13 October 2021
Assigned by
microsoft
CVSS
7.8 High (CVSS 3.1, from the CNA)
CWE-416
Use After Free
CISA SSVC, exploitation
active
CISA SSVC, automatable
no
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

Public exploits

Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.

  • Metasploit: Win32k NtGdiResetDC Use After Free Local Privilege Elevationexploit module, rank good

Windows: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2025-60710Link FollowingMicrosoft WindowsPatch nowRansomware use, listed within a year0.05
CVE-2008-4250Buffer OverflowMicrosoft WindowsPatch this weekMetasploit module; EPSS 0.99; verified Exploit-DB entry0.99
CVE-2008-0015Video ActiveX Control Remote Code ExecutionMicrosoft WindowsPatch this weekMetasploit module; EPSS 0.77; verified Exploit-DB entry0.77
CVE-2013-3918Out-of-Bounds WriteMicrosoft WindowsPatch this weekMetasploit module; EPSS 0.74; verified Exploit-DB entry0.74
CVE-2010-2568Remote Code ExecutionMicrosoft WindowsPatch this weekMetasploit module; EPSS 0.91; verified Exploit-DB entry0.91
CVE-2015-0016TS WebProxy Directory TraversalMicrosoft WindowsPatch this weekMetasploit module; EPSS 0.76; verified Exploit-DB entry0.76
CVE-2015-2426Adobe Type Manager Library Remote Code ExecutionMicrosoft WindowsPatch this weekMetasploit module; EPSS 0.87; verified Exploit-DB entry0.87
CVE-2014-6332Object Linking & Embedding (OLE) Automation Array Remote Code ExecutionMicrosoft WindowsPatch this weekMetasploit module; EPSS 0.95; verified Exploit-DB entry0.95
CVE-2017-0146SMB Remote Code ExecutionMicrosoft WindowsPatch this weekRansomware use; Metasploit module; EPSS 0.90; verified Exploit-DB entry0.90
CVE-2014-4114Object Linking & Embedding (OLE) Remote Code ExecutionMicrosoft WindowsPatch this weekMetasploit module; EPSS 0.82; verified Exploit-DB entry0.82

All 174 entries for Windows

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