# GHSA-cxf7-m5g2-v594: Zend-Mail remote code execution in zend-mail via Sendmail adapter

> Attackers can execute arbitrary commands on the server by injecting parameters into the sendmail binary via crafted email addresses in zend-mail.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Jun 2024

## What is GHSA-cxf7-m5g2-v594?

GHSA-cxf7-m5g2-v594 is a command injection vulnerability in zendframework/zend-mail, published on 7 Jun 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

When using the zend-mail component to send email via the `Zend\Mail\Transport\Sendmail` transport, a malicious user may be able to inject arbitrary parameters to the system sendmail program. The attack is performed by providing additional quote characters within an address; when unsanitized, they can be interpreted as additional command line arguments, leading to the vulnerability.

The following example demonstrates injecting additional parameters to the sendmail binary via the From address:
```
use Zend\Mail;

$mail = new Mail\Message();
$mail->setBody('This is the text of the email.');

// inject additional parameters to sendmail command line
$mail->setFrom('"AAA\" params injection"@domain', 'Sender\'s name');

$mail->addTo('hacker@localhost', 'Name of recipient');
$mail->setSubject('TestSubject');

$transport = new Mail\Transport\Sendmail();
$transport->send($mail);
```
The attack works because zend-mail filters the email addresses using the RFC 3696 specification, where the string "AAA\" params injection"@domain is considered a valid address. This validation is provided using the zend-validator component with the following parameters:
```
Zend\Validator\EmailAddress(
    Zend\Validator\Hostname::ALLOW_DNS | Zend\Validator\Hostname::ALLOW_LOCAL
)
```
The above accepts local domain with any string specified by double quotes as the local part. While this is valid per RFC 3696, due to the fact that sender email addresses are provided to the sendmail binary via the command line, they create the vulnerability described above.

## Which versions are affected by GHSA-cxf7-m5g2-v594?

4 open source packages ship an affected version, including zendframework/zend-mail.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `zendframework/zend-mail` | Packagist | From 2.0.0 | 2.4.11 |
| `zendframework/zend-mail` | Packagist | From 2.0.0 | 2.4.11 |
| `zendframework/zend-mail` | Packagist | From 2.5.0 | 2.7.2 |
| `zendframework/zend-mail` | Packagist | From 2.5.0 | 2.7.2 |

## How do I fix GHSA-cxf7-m5g2-v594?

Upgrade zendframework/zend-mail to a fixed version for your release line: 2.4.11 or 2.7.2.

## Is GHSA-cxf7-m5g2-v594 being exploited?

There is no known exploitation of GHSA-cxf7-m5g2-v594 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-cxf7-m5g2-v594 and fix it if it is affected.

What it is: GHSA-cxf7-m5g2-v594 is a command injection vulnerability in zendframework/zend-mail, published on 7 Jun 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-cxf7-m5g2-v594 in the wild and no public exploit code.

Affected packages and fixed versions:
- zendframework/zend-mail (Packagist): affected from 2.0.0; fixed in 2.4.11
- zendframework/zend-mail (Packagist): affected from 2.0.0; fixed in 2.4.11
- zendframework/zend-mail (Packagist): affected from 2.5.0; fixed in 2.7.2
- zendframework/zend-mail (Packagist): affected from 2.5.0; fixed in 2.7.2

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/GHSA-cxf7-m5g2-v594/ (Markdown: https://insights.sbomify.com/GHSA-cxf7-m5g2-v594/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-cxf7-m5g2-v594

---
From sbomify Insights: https://insights.sbomify.com/GHSA-cxf7-m5g2-v594/
Summaries are generated and may contain mistakes; the official description above is the record.