CVE-2021-33742

ENISA EUVD: EUVD-2021-20419 ↗
Exploited in the Wild ✓ Confirmed 0-Day ★ Google Project Zero
Triaged: March 5, 2026 7 articles Published: 2021-06-08

EPSS Score

Source: FIRST.org · 2026-05-23
72.12%
probability
This CVE has a 72.12% probability of being exploited in the next 30 days.
0% Top 98.8th percentile of all CVEs 100%

CVSS v3.1

Source: VulnerabilityLookup (CIRCL)
7.5
HIGH
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Temporal
Exploit Code Maturity
Functional
Remediation Level
Official Fix
Report Confidence
Confirmed
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

CVSS v2 (legacy)

6.8
MEDIUM
Access Vector
Network
Access Complexity
Medium
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial
AV:N/AC:M/Au:N/C:P/I:P/A:P

Description

NVD
Windows MSHTML Platform Remote Code Execution Vulnerability

Affected Products

Microsoft
Windows 10 Version 1809
10.0.0
Microsoft
Windows Server 2019
10.0.0
Microsoft
Windows 10 Version 1909
10.0.0
Microsoft
Windows 10 Version 21H1
10.0.0
Microsoft
Windows 10 Version 2004
10.0.0

Attack Intelligence

Google Project Zero

Discovered
June 3, 2021
Patched
June 8, 2021
Reported by
Clément Lecigne of Google’s Threat Analysis Group
Root Cause Analysis
https://googleprojectzero.github.io/0days-in-the-wild/0day-RCAs/2021/CVE-2021-33742.html

Signal Intelligence

Confidence
95%
EPSS 72.12%
CVSS v3.1 7.5
Mentions 7
Last Seen Nov 12, 2021

CNA Information

CNA Assigner
microsoft
CNA Title
Windows MSHTML Platform Remote Code Execution Vulnerability

Analyst Note

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

Threat Actors 4

Kinsing
apt_group 🇷🇺 RU
Infy
apt_group Information theft and espionage 🇮🇷 IR
TeamTNT
apt_group 🇩🇪 DE
Tortoiseshell
apt_group Information theft and espionage 🇮🇷 IR

Triage Info

Decided atMar 05, 2026
Published DateJun 08, 2021