8.4

CVE-2021-33739: Microsoft Desktop Window Manager (DWM) Core Library Privilege Escalation Vulnerability

CVSS: 8.4v3.1HighKEVAnalyzed
Published 08-06-2021Last modified 21-10-2025

Vulnerability summary

CVE-2021-33739 is a high (CVSS 8.4) vulnerability in Microsoft Windows. It is known to be exploited: CISA lists it, first on 03-11-2021. EPSS estimates a 6.55% chance of exploitation in the next 30 days, higher than 93.7% of scored vulnerabilities.

Overall risk
85/100
0100
Critical · default modelHow is this calculated?
CVSS score
8.4/10
010
High · v3.1 (CVE.org)
EPSS score
6.55%
0%100%
Low · 0.00 pp in 30 days
KEVListedCISA
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 08-06-2021
    PublishedVulnerability first disclosed.
  2. 03-11-2021
    Added to CISA KEVMicrosoft Desktop Window Manager (DWM) Core Library Privilege Escalation Vulnerability
  3. 17-11-2021
    CISA remediation dueApply updates per vendor instructions.
  4. 21-10-2025
    Last modifiedVulnerability information updated.

Description

Microsoft DWM Core Library Elevation of Privilege Vulnerability

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

6.55%

Chance of exploitation in the next 30 days

Percentile

94%

Versus all other CVEs

30-day change

0.00 pp

From 6.55% on 20-09-2026

20-09-202620-10-2026
EPSS score
6.55%

Known exploited

Compare KEV catalogs
CISA KEVListed
Added
03-11-2021
Federal due date
17-11-2021

CISA required action

Apply updates per vendor instructions. nvd.nist.gov/vuln/detail/CVE-2021-33739

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Microsoft12 products

1 vendor · 12 products

References

2 links