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


- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:F/RL:O/RC:C`)
- **Exploited in the wild:** Yes, since 3 Nov 2021 (CISA KEV), used in ransomware
- **Fix available:** No
- **Published:** 12 Aug 2021
- **Updated:** 10 Aug 2026
- **Also known as:** GHSA-p8qf-gcxq-47xm

## What is CVE-2021-36942?

CVE-2021-36942 is a high-severity vulnerability in Microsoft Windows Server 2008, published on 12 Aug 2021. 

### Official description

Windows LSA Spoofing Vulnerability

## Which versions are affected by CVE-2021-36942?

It affects 6 products.


Products: Microsoft Windows Server 2004, Microsoft Windows Server 2008, Microsoft Windows Server 2012, Microsoft Windows Server 2016, Microsoft Windows Server 2019, Microsoft Windows Server 20h2.

## How do I fix CVE-2021-36942?

No fix has been published for CVE-2021-36942 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 17 Nov 2021.

## Is CVE-2021-36942 being exploited?

Yes. Attackers have exploited CVE-2021-36942 in the wild since at least 3 Nov 2021, including in ransomware campaigns.

Public exploit code:

- PetitPotam (metasploit)

## Other vulnerabilities in Microsoft Windows Server 2008

- [CVE-2021-42278](https://insights.sbomify.com/CVE-2021-42278/): Microsoft Active Directory Domain Services Privilege Escalation (high 7.5, exploited in the wild)
- [CVE-2021-42287](https://insights.sbomify.com/CVE-2021-42287/): Microsoft Active Directory Domain Services Privilege Escalation (high 7.5, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-36942 and fix it if it is affected.

What it is: CVE-2021-36942 is a high-severity vulnerability in Microsoft Windows Server 2008, published on 12 Aug 2021. 
Exploitation: Yes. Attackers have exploited CVE-2021-36942 in the wild since at least 3 Nov 2021, including in ransomware campaigns.

Affected product: Microsoft Windows Server 2008. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2021-36942/ (Markdown: https://insights.sbomify.com/CVE-2021-36942/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-36942
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-36942
- OSV: https://osv.dev/vulnerability/CVE-2021-36942

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-36942/
Summaries are generated and may contain mistakes; the official description above is the record.