CVE-2021-31955: Microsoft Windows Kernel Information Disclosure Vulnerability

CVE-2021-31955 · Severity: critical · CVSS 5.5 · Exploited in the wild · Published 2021-11-03

An information disclosure vulnerability exists in the Microsoft Windows Kernel that allows a local attacker to read the contents of kernel memory from a user-mode process. This flaw can be used to bypass security features by exposing sensitive system information.

Technologies: Microsoft Windows. Vendors: Microsoft.

Quick answers

Is CVE-2021-31955 exploited in the wild?
Yes. CVE-2021-31955 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.
How severe is CVE-2021-31955?
Critical severity, with a CVSS score of 5.5, published 3 November 2021.
Which products and versions are affected?
Microsoft Windows 10 1809, 1909, 2004, 20H2, 21H1; Microsoft Windows Server 2019 -; Microsoft Windows Server 2004, 20H2.
Is there a fix for CVE-2021-31955?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2021-31955 attacked?
It is attacked with local access, in an operating system.
Am I affected by CVE-2021-31955?
Check whether you run Microsoft Windows. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Affected products

  • Microsoft Windows 10 1809, 1909, 2004, 20H2, 21H1
  • Microsoft Windows Server 2019 -
  • Microsoft Windows Server 2004, 20H2

Timeline

  • 2021-06-08: disclosed: NVD Published Date
  • 2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
  • 2021-11-03: exploited: Reported as exploited in the wild in CISA KEV catalog

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