How severe is CVE-2021-34448?

CVE-2021-34448 has a CVSS 3.1 base score of 6.8 (MEDIUM). EPSS estimates a 40.1% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2021-34448: Scripting Engine Memory Corruption

CISA Known Exploited Vulnerabilities

Microsoft Windows Scripting Engine Memory Corruption Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2021-11-03

Remediation due

2021-11-17

Required action
Apply updates per vendor instructions.

CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2021-34448

Description

Scripting Engine Memory Corruption Vulnerability

Severity

CVSS 3.1 · CNA6.8 MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N/E:F/RL:O/RC:C

SSVC · CISA-ADP

Exploitationactive

Automatableyes

Technical impacttotal

Affected Products

Vendor	Product	Affected versions
Microsoft	Windows 10 Version 1507	10.0.10240.0 to <10.0.10240.19003
Microsoft	Windows 10 Version 1607	10.0.14393.0 to <10.0.14393.4530
Microsoft	Windows 10 Version 1809	10.0.17763.0 to <10.0.17763.2061
Microsoft	Windows 10 Version 1809	10.0.0 to <10.0.17763.2061
Microsoft	Windows 10 Version 1909	10.0.0 to <10.0.18363.1679
Microsoft	Windows 10 Version 2004	10.0.0 to <10.0.19041.1110
Microsoft	Windows 10 Version 20H2	10.0.0 to <10.0.19042.1110
Microsoft	Windows 10 Version 21H1	10.0.0 to <10.0.19043.1110
Microsoft	Windows 7	6.1.0 to <6.1.7601.25661
Microsoft	Windows 7 Service Pack 1	6.1.0 to <6.1.7601.25661
Microsoft	Windows 8.1	6.3.0 to <6.3.9600.20069
Microsoft	Windows Server 2008 R2 Service Pack 1	6.1.7601.0 to <6.1.7601.25661
Microsoft	Windows Server 2012	6.2.9200.0 to <6.2.9200.23409
Microsoft	Windows Server 2012 R2	6.3.9600.0 to <6.3.9600.20069
Microsoft	Windows Server 2016	10.0.14393.0 to <10.0.14393.4530
Microsoft	Windows Server 2019	10.0.17763.0 to <10.0.17763.2061

References

2 Links

Vendor advisories

Scripting Engine Memory Corruption Vulnerability

Other references

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34448

Record Details

Published

2021-07-16

Last updated

2026-08-10

Assigner (CNA)

microsoft

Credited to

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.