# CVE-2021-42237: Sitecore XP Remote Command Execution

> Unauthenticated attackers can achieve remote command execution via insecure deserialization in Sitecore XP.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 25 Mar 2022 (CISA KEV), used in ransomware
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 5 Nov 2021
- **Updated:** 9 Jul 2026
- **Also known as:** GHSA-j3x5-fr4h-9v7v

## What is CVE-2021-42237?

CVE-2021-42237 is a critical unsafe deserialization vulnerability in n/a, published on 5 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Sitecore XP 7.5 Initial Release to Sitecore XP 8.2 Update-7 is vulnerable to an insecure deserialization attack where it is possible to achieve remote command execution on the machine. No authentication or special configuration is required to exploit this vulnerability.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2021-42237?

It affects 1 product.


Products: Sitecore Experience Platform.

## How do I fix CVE-2021-42237?

No fix has been published for CVE-2021-42237 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 15 Apr 2022.

## Is CVE-2021-42237 being exploited?

Yes. Attackers have exploited CVE-2021-42237 in the wild since at least 25 Mar 2022, including in ransomware campaigns.

Public exploit code:

- An exploit/PoC for CVE-2021-42237 (github_poc): https://github.com/ItsIgnacioPortal/CVE-2021-42237
- https://github.com/vesperp/CVE-2021-42237-SiteCore-XP (github_poc): https://github.com/vesperp/CVE-2021-42237-SiteCore-XP
- Sitecore Experience Platform (XP) PreAuth Deserialization RCE (metasploit)
- For detection of sitecore RCE - CVE-2021-42237 (github_poc): https://github.com/crankyyash/SiteCore-RCE-Detection
- Sitecore Experience Platform Pre-Auth RCE (nuclei): http/cves/2021/CVE-2021-42237.yaml

## Other vulnerabilities in n/a

- [CVE-2023-27068](https://insights.sbomify.com/CVE-2023-27068/): Deserialization in n/a (critical 9.8)
- [CVE-2023-33652](https://insights.sbomify.com/CVE-2023-33652/): Code injection in n/a (high 8.8)
- [CVE-2023-33653](https://insights.sbomify.com/CVE-2023-33653/): Command injection in n/a (high 8.8)
- [CVE-2019-11080](https://insights.sbomify.com/CVE-2019-11080/): Deserialization in n/a (high 8.8)
- [CVE-2023-27067](https://insights.sbomify.com/CVE-2023-27067/): Path traversal in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-42237 and fix it if it is affected.

What it is: CVE-2021-42237 is a critical unsafe deserialization vulnerability in n/a, published on 5 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2021-42237 in the wild since at least 25 Mar 2022, including in ransomware campaigns.

Affected product: n/a. 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-2021-42237/ (Markdown: https://insights.sbomify.com/CVE-2021-42237/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-42237
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-42237
- OSV: https://osv.dev/vulnerability/CVE-2021-42237

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-42237/
Summaries are generated and may contain mistakes; the official description above is the record.