High severity · published Jun 8, 2021
CVE-2021-33742
Windows MSHTML Platform Remote Code Execution Vulnerability
In wildKEV
7.5
CVSS
59.4%
EPSS
Yes
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)59.4% · higher than 99% of CVEs
Exploited in the wildYes
CISA KEVListed Nov 3, 2021
Federal remediation dueNov 17, 2021
Ransomware campaign useNot known
Affected products
Which versions
WI
Windows · Microsoft
All versions, or not specified · source: KEV
W1
Windows 10 Version 1507 · Microsoft
10.0.0 before 10.0.10240.18967 · source: vendor
W1
Windows 10 Version 1607 · Microsoft
10.0.0 before 10.0.14393.4467 · source: vendor
W1
Windows 10 Version 1809 · Microsoft
10.0.0 before 10.0.17763.1999 · source: vendor
W1
Windows 10 Version 1909 · Microsoft
10.0.0 before 10.0.18363.1621 · source: vendor
W1
Windows 10 Version 2004 · Microsoft
10.0.0 before 10.0.19041.1052 · source: vendor
W1
Windows 10 Version 20H2 · Microsoft
10.0.0 before 10.0.19042.1052 · source: vendor
W1
Windows 10 Version 21H1 · Microsoft
10.0.0 before 10.0.19043.1052 · source: vendor
W7
Windows 7 · Microsoft
6.1.0 before 6.1.7601.25632; 6.1.0 before publication · source: vendor, NVD
W7
Windows 7 Service Pack 1 · Microsoft
6.1.0 before 6.1.7601.25632; 6.1.0 before publication · source: vendor
W8
Windows 8.1 · Microsoft
6.3.0 before 6.3.9600.20045; 6.3.0 before 1.0.0.0 · source: vendor, NVD
WS
Windows Server 2008 Service Pack 2 · Microsoft
6.0.0 before 6.0.6003.21137; 6.0.0 before publication · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-33742
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-33742
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
x_refsource_MISC
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33742
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