# CVE-2021-37840: Cross-site request forgery in n/a

> Cross-Site WebSocket Hijacking in aaPanel allows attackers to execute OS commands if the victim has configured a terminal host.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 2 Aug 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-r4vq-r3rv-8p3p

## What is CVE-2021-37840?

CVE-2021-37840 is a high-severity vulnerability in n/a, published on 2 Aug 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

aaPanel through 6.8.12 allows Cross-Site WebSocket Hijacking (CSWH) involving OS commands within WebSocket messages at a ws:// URL for /webssh (the victim must have configured Terminal with at least one host). Successful exploitation depends on the browser used by a potential victim (e.g., exploitation can occur with Firefox but not Chrome).

## Which versions are affected by CVE-2021-37840?

It affects 1 product.


Products: Aapanel Aapanel.

## How do I fix CVE-2021-37840?

No fix has been published for CVE-2021-37840 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-37840 being exploited?

There is no known exploitation of CVE-2021-37840 in the wild and no public exploit code.

Public exploit code:

- aaPanel WebSocket CSRF Bypass leading to RCE (Incomplete fix for CVE-2021-37840) (github_poc): https://github.com/EonSecurity/aapanel-ws-bypass

## Other vulnerabilities in n/a

- [CVE-2026-29859](https://insights.sbomify.com/CVE-2026-29859/): File upload in n/a (critical 9.8)
- [CVE-2020-14950](https://insights.sbomify.com/CVE-2020-14950/): Command injection in n/a (high 8.8)
- [CVE-2026-29856](https://insights.sbomify.com/CVE-2026-29856/): Denial of service in n/a (high 7.5)
- [CVE-2026-29858](https://insights.sbomify.com/CVE-2026-29858/): Path traversal in n/a (high 7.5)
- [CVE-2020-14421](https://insights.sbomify.com/CVE-2020-14421/): Command injection in n/a (high 7.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-37840 and fix it if it is affected.

What it is: CVE-2021-37840 is a high-severity vulnerability in n/a, published on 2 Aug 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-37840 in the wild and no public exploit code.

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-2021-37840/ (Markdown: https://insights.sbomify.com/CVE-2021-37840/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-37840
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-37840
- OSV: https://osv.dev/vulnerability/CVE-2021-37840

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-37840/
Summaries are generated and may contain mistakes; the official description above is the record.