# CVE-2013-4389: actionmailer email address processing causes Denial of service

> Remote attackers can cause denial of service in Ruby on Rails Action Mailer via crafted email addresses triggering format string errors in logging.

- **Severity:** Medium 4.3 (`AV:N/AC:M/Au:N/C:N/I:N/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Oct 2013
- **Updated:** 6 Aug 2024
- **Also known as:** DSA-2887-1, GHSA-rg5m-3fqp-6px8

## What is CVE-2013-4389?

CVE-2013-4389 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 17 Oct 2013. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Multiple format string vulnerabilities in log_subscriber.rb files in the log subscriber component in Action Mailer in Ruby on Rails 3.x before 3.2.15 allow remote attackers to cause a denial of service via a crafted e-mail address that is improperly handled during construction of a log message.

Weakness: CWE-134 (Use of Externally-Controlled Format String)

## Which versions are affected by CVE-2013-4389?

2 open source packages ship an affected version, including actionmailer. It affects 3 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `actionmailer` | RubyGems | From 3.0.0 | 3.2.15 |
| `actionmailer` | RubyGems | From 3.0.0 | 3.2.15 |

Products: Debian Debian Linux, Opensuse Opensuse, Rubyonrails Rails.

## How do I fix CVE-2013-4389?

Upgrade actionmailer to 3.2.15 or later.

## Is CVE-2013-4389 being exploited?

There is no known exploitation of CVE-2013-4389 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2013-4389 and fix it if it is affected.

What it is: CVE-2013-4389 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 17 Oct 2013. 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-2013-4389 in the wild and no public exploit code.

Affected packages and fixed versions:
- actionmailer (RubyGems): affected from 3.0.0; fixed in 3.2.15
- actionmailer (RubyGems): affected from 3.0.0; fixed in 3.2.15

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-2013-4389/ (Markdown: https://insights.sbomify.com/CVE-2013-4389/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2013-4389
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2013-4389
- OSV: https://osv.dev/vulnerability/CVE-2013-4389

---
From sbomify Insights: https://insights.sbomify.com/CVE-2013-4389/
Summaries are generated and may contain mistakes; the official description above is the record.