# CVE-2021-21433: Remote code execution on discord-recon .dirsearch and .arjun commands due to improper input validation

> Remote attackers can execute arbitrary commands on the Discord Recon Server via improper input validation in specific commands.

- **Severity:** Critical 9.9 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Apr 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-65fm-5x64-gv9x

## What is CVE-2021-21433?

CVE-2021-21433 is a critical command injection vulnerability in DEMON1A Discord-Recon, published on 9 Apr 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Discord Recon Server is a bot that allows you to do your reconnaissance process from your Discord. Remote code execution in version 0.0.1 would allow remote users to execute commands on the server resulting in serious issues. This flaw is patched in 0.0.2.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command), CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2021-21433?

It affects 1 product.


Products: Demon1a Discord-Recon.

## How do I fix CVE-2021-21433?

No fix has been published for CVE-2021-21433 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-21433 being exploited?

There is no known exploitation of CVE-2021-21433 in the wild and no public exploit code.

## Other vulnerabilities in DEMON1A Discord-Recon

- [CVE-2024-21663](https://insights.sbomify.com/CVE-2024-21663/): Remote code execution on ReconServer due to improper input sanitization on the prips command (critical 10.0)
- [CVE-2021-29461](https://insights.sbomify.com/CVE-2021-29461/): LFI and possible code execution on discord-recon using tools arguments (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-21433 and fix it if it is affected.

What it is: CVE-2021-21433 is a critical command injection vulnerability in DEMON1A Discord-Recon, published on 9 Apr 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-21433 in the wild and no public exploit code.

Affected product: DEMON1A Discord-Recon. 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-2021-21433/ (Markdown: https://insights.sbomify.com/CVE-2021-21433/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-21433
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-21433
- OSV: https://osv.dev/vulnerability/CVE-2021-21433

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-21433/
Summaries are generated and may contain mistakes; the official description above is the record.