# CVE-2020-36442: Data races in beef

> The beef crate lacks a Sync bound on Send, potentially allowing unsafe concurrent access and race conditions in Rust applications.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/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:** Not needed
- **Fix available:** Yes
- **Published:** 8 Aug 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-m7w4-8wp8-m2xq, RUSTSEC-2020-0122

## What is CVE-2020-36442?

CVE-2020-36442 is a high-severity vulnerability in n/a, published on 8 Aug 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An issue was discovered in the beef crate before 0.5.0 for Rust. beef::Cow has no Sync bound on its Send trait.

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2020-36442?

3 open source packages ship an affected version, including beef. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `beef` | crates.io | All versions | 0.5.0 |
| `beef` | crates.io | All versions | 0.5.0 |
| `beef` | crates.io | From 0.0.0-0 | 0.5.0 |

Products: Beef Project Beef.

## How do I fix CVE-2020-36442?

Upgrade beef to 0.5.0 or later.

## Is CVE-2020-36442 being exploited?

There is no known exploitation of CVE-2020-36442 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-36442 and fix it if it is affected.

What it is: CVE-2020-36442 is a high-severity vulnerability in n/a, published on 8 Aug 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-36442 in the wild and no public exploit code.

Affected packages and fixed versions:
- beef (crates.io): affected all versions; fixed in 0.5.0
- beef (crates.io): affected all versions; fixed in 0.5.0
- beef (crates.io): affected from 0.0.0-0; fixed in 0.5.0

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-2020-36442/ (Markdown: https://insights.sbomify.com/CVE-2020-36442/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-36442
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-36442
- OSV: https://osv.dev/vulnerability/CVE-2020-36442

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-36442/
Summaries are generated and may contain mistakes; the official description above is the record.