# CVE-2021-3769: OS Command Injection in ohmyzsh/ohmyzsh

> Attackers can execute arbitrary commands via crafted Git branch names in specific Oh My Zsh themes, requiring users to update the framework.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/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:** 30 Nov 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-f8r6-c3hp-ccv4

## What is CVE-2021-3769?

CVE-2021-3769 is a high-severity command injection vulnerability in ohmyzsh/ohmyzsh, published on 30 Nov 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

# Vulnerability in `pygmalion`, `pygmalion-virtualenv` and `refined` themes **Description**: these themes use `print -P` on user-supplied strings to print them to the terminal. All of them do that on git information, particularly the branch name, so if the branch has a specially-crafted name the vulnerability can be exploited. **Fixed in**: [b3ba9978](https://github.com/ohmyzsh/ohmyzsh/commit/b3ba9978). **Impacted areas**: - `pygmalion` theme. - `pygmalion-virtualenv` theme. - `refined` theme.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command)

## Which versions are affected by CVE-2021-3769?

It affects 1 product.


Products: Planetargon Oh My Zsh.

## How do I fix CVE-2021-3769?

No fix has been published for CVE-2021-3769 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-3769 being exploited?

There is no known exploitation of CVE-2021-3769 in the wild and no public exploit code.

## Other vulnerabilities in ohmyzsh/ohmyzsh

- [CVE-2021-3934](https://insights.sbomify.com/CVE-2021-3934/): OS Command Injection in ohmyzsh/ohmyzsh (high 7.8)
- [CVE-2021-3725](https://insights.sbomify.com/CVE-2021-3725/): OS Command Injection in ohmyzsh/ohmyzsh (high 7.5)
- [CVE-2021-3726](https://insights.sbomify.com/CVE-2021-3726/): OS Command Injection in ohmyzsh/ohmyzsh (high 7.5)
- [CVE-2021-3727](https://insights.sbomify.com/CVE-2021-3727/): OS Command Injection in ohmyzsh/ohmyzsh (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-3769 and fix it if it is affected.

What it is: CVE-2021-3769 is a high-severity command injection vulnerability in ohmyzsh/ohmyzsh, published on 30 Nov 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-2021-3769 in the wild and no public exploit code.

Affected product: ohmyzsh/ohmyzsh. 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-2021-3769/ (Markdown: https://insights.sbomify.com/CVE-2021-3769/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-3769
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-3769
- OSV: https://osv.dev/vulnerability/CVE-2021-3769

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-3769/
Summaries are generated and may contain mistakes; the official description above is the record.