CVE-2020-14001 — Unintended read access in kramdown — CVE Details

CRITICAL

Unintended read access in kramdown gem

Published August 7, 2020Updated February 18, 2024Source: osv

Summary

The kramdown gem before 2.3.0 for Ruby processes the template option inside Kramdown documents by default, which allows unintended read access (such as template="/etc/passwd") or unintended embedded Ruby code execution (such as a string that begins with template="string://<%= `). NOTE: kramdown is used in Jekyll, GitLab Pages, GitHub Pages, and Thredded Forum.

Advisory Timeline

First published August 7, 2020 (2257 days ago).
Last revised February 18, 2024 — 1289 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

Bundler

Update kramdown to 2.3.0 or later

gem install kramdown -v 2.3.0

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

Affected Packages (1)

Affects 1 ecosystem: rubygems (1).

Package	Ecosystem	Affected	Fixed In
kramdown	rubygems	0.1.0, 0.10.0, 0.11.0, 0.12.0 (+55 more)	2.3.0

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CWE-862
Missing AuthorizationMITRE

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

References

Frequently Asked Questions

What is CVE-2020-14001?: Unintended read access in kramdown gem 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-2020-14001?: CVE-2020-14001 affects kramdown. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2020-14001 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-mqm2-cgpr-p4m6

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