CVE-2021-34448 kev in the critical feed json
Scripting Engine Memory Corruption Vulnerability
published 2021-07-16 5 y ago modified 2026-08-10 2 mo ago also EUVD-2021-21103
- cvss
- 8.8
- version 3.1, CNA
- cisa kev
- Exploited
- added 2021-11-03
- epss
- 40.1%
- EPSS 40.1% chance of exploitation in 30 days, percentile 98%
- public exploits
- 0
- none known
Summary
Scripting Engine Memory Corruption Vulnerability
Patch / fix
cisa required action Apply updates per vendor instructions.
- Microsoft Windows 10 Version 1507 10.0.10240.19003
- Microsoft Windows 10 Version 1607 10.0.14393.4530
- Microsoft Windows 10 Version 1809 10.0.17763.2061
- Microsoft Windows 10 Version 1909 10.0.18363.1679
- Microsoft Windows 10 Version 2004 10.0.19041.1110
- Microsoft Windows 10 Version 20H2 10.0.19042.1110
- Microsoft Windows 10 Version 21H1 10.0.19043.1110
- Microsoft Windows 7 6.1.7601.25661
- Microsoft Windows 7 Service Pack 1 6.1.7601.25661
- Microsoft Windows 8.1 6.3.9600.20069
- Microsoft Windows Server 2008 R2 Service Pack 1 6.1.7601.25661
- Microsoft Windows Server 2012 6.2.9200.23409
- Microsoft Windows Server 2012 R2 6.3.9600.20069
- Microsoft Windows Server 2016 10.0.14393.4530
- Microsoft Windows Server 2019 10.0.17763.2061
Timeline
- 0-day patched (Project Zero)
- Published
- Added to CISA KEV
- CISA patch deadline
- CISA SSVC: exploitation active
Known exploited
- Added
- 5 y ago
- Patch by
- 2021-11-17 (4 y ago)
- Ransomware
- Not known
- Required action
- Apply updates per vendor instructions.
- Vendor, product
- Microsoft, Windows
- CISA name
- Microsoft Windows Scripting Engine Memory Corruption Vulnerability
Zero-day
Detected in real attacks while still unknown to the vendor and the public, per Google Project Zero's 0day In-the-Wild tracker.
- Patched
- 2021-07-13
- Details
- project zero tracker
CISA SSVC
- Exploitation
- Active, exploited in the wild
- Automatable
- yes
- Technical impact
- total
- Assessed
- 21 mo ago
Exploit prediction
40.06% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.8 | 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 |
| CNA | 3.1 | 6.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N |
| CNA | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 9.3 | AV:N/AC:M/Au:N/C:C/I:C/A:C |
Affected products
- Microsoft Windows 10 Version 1507
- Microsoft Windows 10 Version 1607
- Microsoft Windows 10 Version 1809
- Microsoft Windows 10 Version 1909
- Microsoft Windows 10 Version 2004
- Microsoft Windows 10 Version 20H2
- Microsoft Windows 10 Version 21H1
- Microsoft Windows 7
- Microsoft Windows 7 Service Pack 1
- Microsoft Windows 8.1
- Microsoft Windows Server 2008 R2 Service Pack 1
- Microsoft Windows Server 2012
- Microsoft Windows Server 2012 R2
- Microsoft Windows Server 2016
- Microsoft Windows Server 2019
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2021-34448
vendor-advisory, patch
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2021-34448
patch, vendor-advisory
-
cisa.gov
/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-34448
government-resource, us-government-resource
Sources
- CVE List CVE-2021-34448
- NVD CVE-2021-34448
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