# CVE-2018-3766: buttle path traversal

Source: https://junglewise.ai/threats/cve-2018-3766-buttle-path-traversal  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2018-09-18. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2018-3766 · Severity: low · CVSS 3.1 · Published 2018-09-18

buttle is a Node.js library for serving files from a server. A path traversal vulnerability allows attackers to access sensitive server files by using relative paths in file requests, bypassing intended directory restrictions. No patch is available, and users are advised to switch to alternative libraries.

Technologies: [buttle (npm)](https://junglewise.ai/threats/technologies/buttle). Vendors: [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2018-3766 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2018-3766 being exploited in the wild.

**How severe is CVE-2018-3766?** Low severity, with a CVSS score of 3.1, published 18 September 2018.

**Which products and versions are affected?** buttle (npm) SEMVER:introduced=0,last_affected=0.2.0.

**Is there a fix for CVE-2018-3766?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2018-3766 attacked?** It is attacked over the network.

**Am I affected by CVE-2018-3766?** Check whether you run buttle (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a classic path traversal (CWE-22) caused by insufficient input sanitization when processing file fetch requests. An unauthenticated attacker on the network can craft requests using relative paths (e.g., "../../../etc/passwd") to escape the intended file serving directory and read arbitrary files from the server. The attack requires no authentication, user interaction, or special conditions. All versions up to and including 0.2.0 are affected. No fix is currently available.

## Affected products

- buttle buttle 0.2.0 and earlier

## Identifiers

- CVE-2018-3766
- GHSA-m8cr-q935-8j67

## Timeline

- 2018-07-05: disclosed
- 2018-09-18: advisory

## References

- [https://hackerone.com/reports/358112](https://hackerone.com/reports/358112)

## Related threats

- [buttle cross-site scripting in markdown rendering](https://junglewise.ai/threats/buttle-cross-site-scripting-in-markdown-rendering-9a0d6176)
- [buttle Cross-Site Scripting in filename sanitization](https://junglewise.ai/threats/cve-2019-5422-buttle-cross-site-scripting-in-filename-sanitization)