# CVE-2021-36942: Microsoft Windows Local Security Authority (LSA) Spoofing Vulnerability

Source: https://junglewise.ai/threats/cve-2021-36942-microsoft-windows-local-security-authority-lsa-spoofing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-11-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2021-36942 · Severity: critical · CVSS 7.5 · Exploited in the wild · Published 2021-11-03

A spoofing vulnerability in the Microsoft Windows Local Security Authority (LSA) allows an unauthenticated attacker to call a method on the LSARPC interface. This can be used to coerce a domain controller to authenticate against a remote server using NTLM, facilitating further attacks.

Technologies: [Microsoft Windows](https://junglewise.ai/threats/technologies/windows). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2021-36942 exploited in the wild?** Yes. CVE-2021-36942 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2021-36942?** Critical severity, with a CVSS score of 7.5, published 3 November 2021.

**Which products and versions are affected?** Microsoft Windows Server 2008 Service Pack 2; Microsoft Windows Server 2008 R2 Service Pack 1; Microsoft Windows Server 2012; Microsoft Windows Server 2012 R2; and 4 more.

**Is there a fix for CVE-2021-36942?** 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-2021-36942 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2021-36942?** 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 Server 2008 Service Pack 2
- Microsoft Windows Server 2008 R2 Service Pack 1
- Microsoft Windows Server 2012
- Microsoft Windows Server 2012 R2
- Microsoft Windows Server 2016 up to (excluding) 10.0.14393.4583
- Microsoft Windows Server 2019 up to (excluding) 10.0.17763.2114
- Microsoft Windows Server 2004 up to (excluding) 10.0.19041.1165
- Microsoft Windows Server 20H2 up to (excluding) 10.0.19042.1165

## Timeline

- 2021-08-12: disclosed: NVD Published Date
- 2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2021-11-03: advisory: Advisory published date provided in report
- 2021-11-17: other: CISA Due Date for remediation

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