What is CVE-2018-8779?

CVE-2018-8779 is a high-severity vulnerability in Ruby-Lang Ruby, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2018-04-03.

How severe is CVE-2018-8779?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2018-8779 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Improper input validation in Ruby-Lang Ruby

CVE-2018-8779

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 UNIXServer.open and UNIXSocket.open methods are not checked for null characters. It may be connected to an unintended socket.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2018-04-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.069 (93.9th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 94th percentile — 93.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.070 · newest: 0.069 · change: -0.001

Affected products

Ruby-Lang Ruby — versions 2.6.0
Canonical Ubuntu Linux — versions 14.04, 16.04, 17.10
Debian Linux — versions 7.0, 8.0, 9.0

Weakness classification (CWE)

CWE-20 — Improper Input Validation

Public proof-of-concept exploits

ARPSyndicate/cvemon

References

www.ruby-lang.org/en/news/2018/03/28/ruby-2-5-1-released/ (Patch, Vendor Advisory)
access.redhat.com/errata/RHSA-2018:3729 (vendor-advisory, Third Party Advisory)
usn.ubuntu.com/3626-1/ (vendor-advisory, Third Party Advisory)
www.securitytracker.com/id/1042004 (VDB Entry, Third Party Advisory, vdb-entry)
access.redhat.com/errata/RHSA-2018:3730 (vendor-advisory, Third Party Advisory)
lists.debian.org/debian-lts-announce/2018/04/msg00023.html (mailing-list, Mailing List, Third Party Advisory)
access.redhat.com/errata/RHSA-2018:3731 (vendor-advisory, Third Party Advisory)
www.ruby-lang.org/en/news/2018/03/28/ruby-2-3-7-released/ (Patch, Vendor Advisory)
www.securityfocus.com/bid/103767 (VDB Entry, Third Party Advisory, vdb-entry)
lists.debian.org/debian-lts-announce/2018/07/msg00012.html (mailing-list, Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2018-8779?: CVE-2018-8779 is a high-severity vulnerability in Ruby-Lang Ruby, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2018-04-03.
How severe is CVE-2018-8779?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2018-8779 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.