CVE-2017-6181: Ruby-Lang Ruby

High severity, CVSS 7.5. EPSS: 3.6% chance of exploitation in the next 30 days.

The parse_char_class function in regparse.c in the Onigmo (aka Oniguruma-mod) regular expression library, as used in Ruby 2.4.0, allows remote attackers to cause a denial of service (deep recursion and application crash) via a crafted regular expression.

Affected products

• Ruby-Lang Ruby: version 2.4.0 only

Published 2017-04-03. Last modified 2026-06-17.