CVE-2020-14001: The kramdown gem before 2.3.0 for Ruby processes the template option inside Kramdown documents by default, whi

Q: How do I fix CVE-2020-14001?

kramdown: upgrade to 2.3.0; debian linux: mitigate or apply the listed mitigation; fedora: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Q: Is CVE-2020-14001 being exploited?

CVE-2020-14001 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2020-14001 affect?

CVE-2020-14001 affects kramdown, debian linux, fedora. Severity is critical (CVSS 9.8). 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 tha

Q: How urgent is CVE-2020-14001?

Priority 67/100. Critical severity; EPSS top 8%: very likely to be exploited; Remotely exploitable, no login, no user action; On your watchlist

This week

CRITICAL 9.8REMOTEWATCHLISTUPGRADEMITIGATEMITIGATE

CVE-2020-14001 is a critical-severity flaw (CVSS 9.8) affecting kramdown, debian linux, fedora. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

Critical severity
EPSS top 8%: very likely to be exploited
Remotely exploitable, no login, no user action
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	4.6% (top 8%)
CISA exploited list	No
Weakness	CWE-862
Published	2020-07-17
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: canonical · debian · fedoraproject · kramdown project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2020-07-17 16:15 UTCPublished CVE record published
2026-06-17 02:54 UTCUpdated Record last modified

kramdown project kramdown UPGRADE

Affected: < 2.3.0

Fixed in: 2.3.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy kramdown || rpm -q kramdown || kramdown --version

2. UPGRADE to 2.3.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade kramdown

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade kramdown

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

debian debian linux MITIGATE

Affected: 9.0 · 10.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 9.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

fedoraproject fedora MITIGATE

Affected: 31 · 32

Fixed in: no fixed release known

Safe to downgrade to: a release before 31

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

canonical ubuntu linux MITIGATE

Affected: 20.04

Fixed in: no fixed release known

Safe to downgrade to: a release before 20.04

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2020-14001?

kramdown: upgrade to 2.3.0; debian linux: mitigate or apply the listed mitigation; fedora: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2020-14001 being exploited?

CVE-2020-14001 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2020-14001 affect?

CVE-2020-14001 affects kramdown, debian linux, fedora. Severity is critical (CVSS 9.8). 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 tha

How urgent is CVE-2020-14001?

Priority 67/100. Critical severity; EPSS top 8%: very likely to be exploited; Remotely exploitable, no login, no user action; On your watchlist

Software pages

GitLab vulnerabilities · GitHub vulnerabilities · Ubuntu vulnerabilities · Debian vulnerabilities · Ruby vulnerabilities

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References

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