HOMEVULNERABILITIESCVE-2021-33739
HIGHCISA KEVIN THE WILD

CVE-2021-33739

Published: November 3, 2021

EPSS:19.49%probability of exploitation in 30 daysPercentile:95.3th

Official Description

Microsoft Desktop Window Manager (DWM) Core Library contains an unspecified vulnerability that allows for privilege escalation.

NVD Source

CISA KEV Advisory

Microsoft Desktop Window Manager (DWM) Core Library Privilege Escalation Vulnerability

Microsoft Desktop Window Manager (DWM) Core Library contains an unspecified vulnerability that allows for privilege escalation.

Added to KEV: 2021-11-03Federal patch deadline: 2021-11-17
Required Action (CISA)

Apply updates per vendor instructions.

Risk Analysis

Microsoft Desktop Window Manager (DWM) Core Library contains an unspecified vulnerability that allows for privilege escalation. This high-severity flaw has an EPSS score of 0.19488, indicating a considerable likelihood of exploitation, and CISA has confirmed its active exploitation.

This vulnerability is actively exploited in the wild and is included in CISA's KEV catalog, confirming its use for privilege escalation.

Recommended Action

Install the latest security updates for Microsoft Windows to patch the DWM Core Library privilege escalation vulnerability. Implement the principle of least privilege for all user accounts.

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-2021-33739 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-2021-33739 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.

Affected Vendors & Products

Mentioned vendors (from description):
Microsoft
CPE data not yet available in NVD for this CVE.

Exploit & PoC Resources

ACTIVE EXPLOITATIONConfirmed exploitation in the wild
External links open in a new tab. Always verify in a controlled environment before use.

All References (1)

Quick Facts

CVE IDCVE-2021-33739
SeverityHIGH
CISA KEVYES — Active Exploitation
ExploitIN THE WILD
EPSS (30d)19.49%
PublishedNov 3, 2021

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2021-33739 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
  • !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
  • !Active exploitation confirmed — treat as P1
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.