Junglewise Threat Intelligence

CVE-2021-33742: Microsoft Windows MSHTML Platform Remote Code Execution Vulnerability

CVE-2021-33742 · Severity: critical · CVSS 8.8 · Exploited in the wild · Published 2021-11-03

Technologies: Microsoft Windows, Microsoft Windows 8.1, Microsoft Windows Server 2016, Microsoft Windows Server 2019, Microsoft Windows Server 2008, Microsoft Windows 7, Microsoft Windows 10, Microsoft Windows Server 2012, Microsoft Windows Rt 8.1. Vendors: Microsoft.

Executive brief

Microsoft Windows MSHTML Platform contains an out-of-bounds write vulnerability (CWE-787) that allows for remote code execution. The vulnerability is triggered when a user visits a specially crafted website or opens a malicious file, leading to memory corruption.

Affected products

  • Microsoft Windows 10 1507, 1607, 1809, 1909, 2004, 20H2, 21H1
  • Microsoft Windows 7 SP1
  • Microsoft Windows 8.1
  • Microsoft Windows RT 8.1
  • Microsoft Windows Server 2008 R2 SP1, SP2
  • Microsoft Windows Server 2012 R2
  • Microsoft Windows Server 2016 2004, 20H2, 1909
  • Microsoft Windows Server 2019

Timeline

  • 2021-06-14: disclosed: Initial analysis by NIST
  • 2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
  • 2021-11-03: advisory: Published date listed in advisory
  • 2021-11-03: exploited: Reported as exploited in the wild in CISA KEV catalog

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