CVE-2021-41379: Microsoft Windows Installer Privilege Escalation Vulnerability

CVE-2021-41379 · Severity: critical · CVSS 7.8 · Exploited in the wild · Published 2022-03-03

Microsoft Windows Installer contains a privilege escalation vulnerability caused by improper link resolution before file access (link following). An attacker with local access can exploit this to gain elevated system privileges.

Technologies: Microsoft Windows. Vendors: Microsoft.

Quick answers

Is CVE-2021-41379 exploited in the wild?
Yes. CVE-2021-41379 is known to be exploited in the wild, first recorded on 3 March 2022. Treat it as urgent.
How severe is CVE-2021-41379?
Critical severity, with a CVSS score of 7.8, published 3 March 2022.
Which products and versions are affected?
Microsoft Windows 10 up to (excluding) 10.0.19043.1348; Microsoft Windows 11 up to (excluding) 10.0.22000.318; Microsoft Windows Server 2022 up to (excluding) 10.0.20348.350; Microsoft Windows 7 SP1; and 2 more.
Is there a fix for CVE-2021-41379?
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-2021-41379 attacked?
It is attacked with local access, in an operating system.
Am I affected by CVE-2021-41379?
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 up to (excluding) 10.0.19043.1348
  • Microsoft Windows 11 up to (excluding) 10.0.22000.318
  • Microsoft Windows Server 2022 up to (excluding) 10.0.20348.350
  • Microsoft Windows 7 SP1
  • Microsoft Windows 8.1
  • Microsoft Windows Server 2019 up to (excluding) 10.0.17763.2300

Timeline

  • 2021-11-09: disclosed: Initial Microsoft advisory publication date (implied by CVE year and patch cycle)
  • 2022-03-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
  • 2022-03-03: exploited: Confirmed exploited in the wild per CISA KEV catalog.

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