CVE-2018-16395
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.
Key facts
- CVSS score
- 9.8 (v3.0)
- Severity
- CRITICAL
- CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- EPSS score
- 10.7% (96th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2022-4596)
- Published
- November 16, 2018
- NVD last modified
- June 17, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2022-4596 in the EU Vulnerability Database. Last updated in EUVD on August 5, 2024.
View on the EU Vulnerability DatabaseAffected products
- canonical / ubuntu linux
- canonical / ubuntu linux
- canonical / ubuntu linux
- canonical / ubuntu linux
- debian / debian linux
- debian / debian linux
- redhat / enterprise linux
- ruby-lang / openssl
- ruby-lang / ruby
- ruby-lang / ruby
- ruby-lang / ruby
Certified products that may be affected
7 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.
- Red Hat Enterprise Linux 7 NSS Cryptographic Module - Red Hat®, Inc. - FIPS 140 4498 - historical
- Red Hat Enterprise Linux 7 Kernel Crypto API Cryptographic Module - Red Hat®, Inc. - FIPS 140 3939 - historical
- Red Hat Enterprise Linux 7 OpenSSH Server Cryptographic Module - Red Hat®, Inc. - FIPS 140 3891 - historical
- Red Hat Enterprise Linux 7 OpenSSH Client Cryptographic Module - Red Hat®, Inc. - FIPS 140 3892 - historical
- Red Hat Enterprise Linux 7 OpenSSL Cryptographic Module - Red Hat®, Inc. - FIPS 140 3867 - historical
See all 7 in the Security Certifications Explorer.
References
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00036.html(Mailing List, Third Party Advisory)
- http://www.securitytracker.com/id/1042105(Third Party Advisory, VDB Entry)
- https://access.redhat.com/errata/RHSA-2018:3729(Third Party Advisory)
- https://access.redhat.com/errata/RHSA-2018:3730(Third Party Advisory)
- https://access.redhat.com/errata/RHSA-2018:3731(Third Party Advisory)
- https://access.redhat.com/errata/RHSA-2018:3738(Third Party Advisory)
- https://access.redhat.com/errata/RHSA-2019:1948(Third Party Advisory)
- https://access.redhat.com/errata/RHSA-2019:2565
- https://hackerone.com/reports/387250(Patch, Third Party Advisory)
- https://lists.debian.org/debian-lts-announce/2018/10/msg00020.html(Third Party Advisory)
- https://security.netapp.com/advisory/ntap-20190221-0002/(Third Party Advisory)
- https://usn.ubuntu.com/3808-1/(Third Party Advisory)
- https://www.debian.org/security/2018/dsa-4332(Third Party Advisory)
- https://www.oracle.com/security-alerts/cpujan2020.html
- 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://www.ruby-lang.org/en/news/2018/10/17/ruby-2-3-8-released/(Release Notes, Vendor Advisory)
- https://www.ruby-lang.org/en/news/2018/10/17/ruby-2-4-5-released/(Release Notes, Vendor Advisory)
- https://www.ruby-lang.org/en/news/2018/10/17/ruby-2-5-2-released/(Release Notes, Vendor Advisory)
- https://www.ruby-lang.org/en/news/2018/11/06/ruby-2-6-0-preview3-released/(Release Notes, Vendor Advisory)
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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