CISA KEV catalog
Confirmed active exploitation.
Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.
- Name
- Microsoft Internet Explorer Memory Corruption Vulnerability
- Added to catalog
- Remediation due date (US federal)
- Required action
- Apply updates per vendor instructions.
Description
Internet Explorer Memory Corruption Vulnerability
Affected products
microsoft: edge; microsoft: windows 10 1507; microsoft: windows 10 1607; microsoft: windows 10 1803; microsoft: windows 10 1809; microsoft: windows 10 1903; microsoft: windows 10 1909; microsoft: windows 10 2004; microsoft: windows 10 20h2; microsoft: windows server 2016; microsoft: windows server 2019; microsoft: internet explorer; microsoft: windows 7; microsoft: windows 8.1; microsoft: windows rt 8.1
References3
- msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26411 PatchVendor Advisory
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-… PatchVendor Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=… US Government Resource
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L - EPSS — exploit probability
- 82% percentile: 100 · as of 2 November 2026
- CWE
- CWE-416
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