CVE-2018-16395

Description

An issue was discovered in the OpenSSL library in Ruby before 2.3.8, 2.4.x before 2.4.5, 2.5.x before 2.5.2, and 2.6.x before 2.6.0-preview3. When two OpenSSL::X509::Name objects are compared using ==, depending on the ordering, non-equal objects may return true. When the first argument is one character longer than the second, or the second argument contains a character that is one less than a character in the same position of the first argument, the result of == will be true. This could be leveraged to create an illegitimate certificate that may be accepted as legitimate and then used in signing or encryption operations.

9.8
CVSS
Severity: Critical
CVSS 3.0 •
CVSS 2.0 •
EPSS 8.06% Top 10%
Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory debian.org Vendor Advisory ubuntu.com Vendor Advisory opensuse.org Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory ruby-lang.org Vendor Advisory ruby-lang.org Vendor Advisory ruby-lang.org Vendor Advisory ruby-lang.org Vendor Advisory ruby-lang.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://www.ruby-lang.org/en/news/2018/10/17/openssl-x509-name-equality-check-does-not-work-correctly-cve-2018-16395/ mitigation vendor advisory
https://access.redhat.com/errata/RHSA-2018:3738 third party advisory vendor advisory
https://www.ruby-lang.org/en/news/2018/11/06/ruby-2-6-0-preview3-released/ release notes vendor advisory
https://access.redhat.com/errata/RHSA-2018:3729 third party advisory vendor advisory
https://hackerone.com/reports/387250 third party advisory patch
https://access.redhat.com/errata/RHSA-2018:3730 third party advisory vendor advisory
https://access.redhat.com/errata/RHSA-2018:3731 third party advisory vendor advisory
https://www.ruby-lang.org/en/news/2018/10/17/ruby-2-3-8-released/ release notes vendor advisory
https://www.debian.org/security/2018/dsa-4332 third party advisory vendor advisory
https://usn.ubuntu.com/3808-1/ third party advisory vendor advisory
https://www.ruby-lang.org/en/news/2018/10/17/ruby-2-4-5-released/ release notes vendor advisory
https://security.netapp.com/advisory/ntap-20190221-0002/ third party advisory
https://www.ruby-lang.org/en/news/2018/10/17/ruby-2-5-2-released/ release notes vendor advisory
https://lists.debian.org/debian-lts-announce/2018/10/msg00020.html third party advisory mailing list
http://www.securitytracker.com/id/1042105 vdb entry third party advisory
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00036.html mailing list third party advisory vendor advisory
https://access.redhat.com/errata/RHSA-2019:1948 third party advisory vendor advisory
https://access.redhat.com/errata/RHSA-2019:2565 vendor advisory
https://www.oracle.com/security-alerts/cpujan2020.html

Frequently Asked Questions

What is the severity of CVE-2018-16395?
CVE-2018-16395 has been scored as a critical severity vulnerability.
How to fix CVE-2018-16395?
To fix CVE-2018-16395, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-16395 being actively exploited in the wild?
It is possible that CVE-2018-16395 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~8% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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