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Fencer Intel
high 7.5

CVE-2017-6181 json

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 rem…

published 9y ago modified 4mo ago also EUVD-2017-15246

cvss
7.5
version 3.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
3.6%
EPSS 3.6% chance of exploitation in 30 days, percentile 89%
public exploits
0
none known

Summary

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.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2017-6181 updated cvss 6.5

ruby: Stack overflow in parse_char_class() in Onigmo

  • Red Hat Software Collections rh-ruby24-ruby, rh-ruby24-ruby-irb, rh-ruby24-rubygems, rh-ruby24-ruby-libs, rh-ruby24-rubygem-json, rh-ruby24-rubygem-rake, +11 more
    affected: no fix planned “Will not fix”
  • Red Hat CloudForms Management Engine 5 ruby-200-ruby, rh-ruby22-ruby Red Hat Enterprise Linux 5 ruby Red Hat Enterprise Linux 6 ruby, ruby-ri, ruby-irb, ruby-libs, ruby-rdoc, ruby-tcltk Red Hat Enterprise Linux 7 ruby, ruby-irb, rubygems, ruby-libs, ruby-tcltk, rubygem-json, +6 more Red Hat Software Collections rh-ruby22-ruby, rh-ruby23-ruby, rh-ruby22-ruby-irb, rh-ruby22-rubygems, rh-ruby23-ruby-irb, rh-ruby23-rubygems, +24 more Red Hat Subscription Asset Manager ruby193-ruby
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

3.65% chance of exploitation in the next 30 days, higher than 89% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.0 7.5 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

Classification

Weakness
  • CWE-20 Improper Input Validation

References

Sources

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