CVE-2021-34448
Exploited in the wild. In CISA KEV since 2021‑11‑03. Fixed versions are out.
What to do
Find your product and version, then upgrade to the build on the right.
- Microsoft Windows 10 Version 1507Affected: ≥ 10.0.10240.0, < 10.0.10240.19003Upgrade to: 10.0.10240.19003Affected: ≥ 10.0.14393.0, < 10.0.14393.4530Upgrade to: 10.0.14393.4530Affected: ≥ 10.0.17763.0, < 10.0.17763.2061Upgrade to: 10.0.17763.2061Affected: ≥ 10.0.0, < 10.0.18363.1679Upgrade to: 10.0.18363.1679 + 3 more branchesStated by: CVE record
- Microsoft Windows 7Affected: ≥ 6.1.0, < 6.1.7601.25661Upgrade to: 6.1.7601.25661Stated by: CVE record
- Microsoft Windows 8.1Affected: ≥ 6.3.0, < 6.3.9600.20069Upgrade to: 6.3.9600.20069Stated by: CVE record
- Microsoft Windows Server 2008 R2 Service Pack 1Affected: ≥ 6.1.7601.0, < 6.1.7601.25661Upgrade to: 6.1.7601.25661Stated by: CVE record
- Microsoft Windows Server 2012Affected: ≥ 6.2.9200.0, < 6.2.9200.23409Upgrade to: 6.2.9200.23409Stated by: CVE record
Versions as the sources state them. 3 more products have version data. Full version matrix after sign-in
Coverage timeline
0 publishersAdded to CISA KEV catalog
Sourced from public security reporting — each date is when it was published, not when it happened.
What it is
From the CVE record
Scripting Engine Memory Corruption Vulnerability
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Listed as exploited in the wild since 2021-11-03.
US federal agencies must remediate by 2021-11-17.
Apply updates per vendor instructions.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
40% chance of exploitation activity in the next 30 days, which ranks it in the 99th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
10 events over 1851 days, from the signal feeds we watch.
- Patch availablerecord updated
- OpenVAS check added
- EPSS band changelow → moderate
- Patch availablerecord updated
- Added to CISA KEV
- Publishedweakness classified, att&ck mapped
Affected products
- Windows 10 Version 1507Operating Systems / windows
- Windows 7 Service Pack 1Operating Systems / windows
- Windows 8.1Operating Systems / windows
- Windows Server 2008 R2 Service Pack 1Operating Systems / windows
- Windows Server 2012Operating Systems / windows
- Windows Server 2012 R2Operating Systems / windows
- Windows Server 2016Operating Systems / windows
- Windows Server 2019Operating Systems / windows
And 36 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Scored 6.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity HighRequires specific conditions like a race condition or non-default configuration
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction RequiredA user must click a link, open a file, or perform some action
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Initial AccessT1190Exploit Public-Facing Applicationhigh confidence
- Privilege EscalationT1068Exploitation for Privilege Escalationhigh confidence
Sources
Watch the software you run.
My Stack ranks new CVEs for your products by real-world exploitation, so the next exploited one reaches you without reading every advisory.
We'll flag the next CVE, public exploit or patch for Windows 10 Version 1507, not every advisory. This one: actively exploited.
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- The full version matrix and every affected product
- Exploit links, proofs of concept and Metasploit modules
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