# CVE-2018-3809: Information Exposure on Case Insensitive File Systems in serve

> An attacker can access ignored files and directory listings in the serve package, leading to unauthorized information disclosure.

- **Severity:** Medium 5.3 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 Jun 2018
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-686g-3xr3-x4x6

## What is CVE-2018-3809?

CVE-2018-3809 is a medium-severity vulnerability in n/a, published on 1 Jun 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Information exposure through directory listings in serve 6.5.3 allows directory listing and file access even when they have been set to be ignored.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2018-3809?

2 open source packages ship an affected version, including serve. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `serve` | npm | All versions | 7.0.0 |
| `serve` | npm | All versions | 7.0.0 |

Products: Zeit Serve.

## How do I fix CVE-2018-3809?

Upgrade serve to 7.0.0 or later.

## Is CVE-2018-3809 being exploited?

There is no known exploitation of CVE-2018-3809 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2019-5415](https://insights.sbomify.com/CVE-2019-5415/): Path Traversal in serve (high 7.5)
- [CVE-2019-5417](https://insights.sbomify.com/CVE-2019-5417/): Directory Traversal in serve (high 7.5)
- [CVE-2018-3712](https://insights.sbomify.com/CVE-2018-3712/): Directory Traversal in serve (medium 6.5)
- [CVE-2018-3718](https://insights.sbomify.com/CVE-2018-3718/): vercel/serve allows access to restricted files if filename is URL encoded. (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-3809 and fix it if it is affected.

What it is: CVE-2018-3809 is a medium-severity vulnerability in n/a, published on 1 Jun 2018. 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-2018-3809 in the wild and no public exploit code.

Affected packages and fixed versions:
- serve (npm): affected all versions; fixed in 7.0.0
- serve (npm): affected all versions; fixed in 7.0.0

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-2018-3809/ (Markdown: https://insights.sbomify.com/CVE-2018-3809/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-3809
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-3809
- OSV: https://osv.dev/vulnerability/CVE-2018-3809

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-3809/
Summaries are generated and may contain mistakes; the official description above is the record.