CVE-2021-21306

Name: CVE-2021-21306
Creator: NVD / NIST
Published: 2021-02-08T22:15:12.45+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 2.46%

Last modified Jun 17, 2026

CVE-2021-21306 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Marked is an open-source markdown parser and compiler (npm package "marked"). In marked from version 1.1.1 and before version 2.0.0, there is a Regular expression Denial of Service vulnerability. EPSS estimates a 2.46% chance of exploitation in the next 30 days.

Description

Marked is an open-source markdown parser and compiler (npm package "marked"). In marked from version 1.1.1 and before version 2.0.0, there is a Regular expression Denial of Service vulnerability. This vulnerability can affect anyone who runs user generated code through marked. This vulnerability is fixed in version 2.0.0.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

2.46%

82.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Marked Project	Marked	>= 1.1.1, < 2.0.0

References

https://github.com/markedjs/marked/commit/7293251c438e3ee968970f7609f1a27f9007bccdPatch, Third Party Advisory
https://github.com/markedjs/marked/issues/1927Third Party Advisory
https://github.com/markedjs/marked/pull/1864Patch, Third Party Advisory
https://github.com/markedjs/marked/security/advisories/GHSA-4r62-v4vq-hr96Third Party Advisory
https://www.npmjs.com/package/markedProduct, Third Party Advisory
https://github.com/markedjs/marked/commit/7293251c438e3ee968970f7609f1a27f9007bccdPatch, Third Party Advisory
https://github.com/markedjs/marked/issues/1927Third Party Advisory
https://github.com/markedjs/marked/pull/1864Patch, Third Party Advisory
https://github.com/markedjs/marked/security/advisories/GHSA-4r62-v4vq-hr96Third Party Advisory
https://www.npmjs.com/package/markedProduct, Third Party Advisory

Timeline

Published: Feb 8, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-21306?

How severe is CVE-2021-21306?

CVE-2021-21306 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 2.46% probability of exploitation in the next 30 days.

How do I fix CVE-2021-21306?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-21306?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST