CVE-2018-16395 — Vulnerability in openssl — CVE Details

CRITICAL

Ruby Openssl Allows Incorrect Value Comparison

Published May 13, 2022Updated December 3, 2024Source: osv

Summary

An issue was discovered in the OpenSSL library in Ruby 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.

Advisory Timeline

First published May 13, 2022 (1613 days ago).
Last revised December 3, 2024 — 935 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

Bundler

Update openssl to 2.1.2 or later

gem install openssl -v 2.1.2

Bundler

Update openssl to 2.0.9 or later

gem install openssl -v 2.0.9

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (2)

Affects 1 ecosystem: rubygems (1).

Package	Ecosystem	Affected	Fixed In
openssl	rubygems	2.1.0, 2.1.1	2.1.2
openssl	rubygems	2.0.0, 2.0.0.beta.1, 2.0.0.beta.2, 2.0.1 (+7 more)	2.0.9

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 9.8 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Frequently Asked Questions

What is CVE-2018-16395?: Ruby Openssl Allows Incorrect Value Comparison This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 9.8/10).
How do I check if my project is affected by CVE-2018-16395?: CVE-2018-16395 affects openssl. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2018-16395 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

9.8

Exploitation is straightforward and causes maximum impact. Patch immediately.

Also Known As

GHSA-mmrq-6999-72v8

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