CVE-2021-21306 Denial of Service in Marked
Attackers can cause denial of service in applications using the Marked library by submitting specially crafted markdown input.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-21306?
CVE-2021-21306 is a medium-severity denial of service vulnerability in markedjs marked, published on 8 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-400
Which versions are affected by CVE-2021-21306?
2 open source packages ship an affected version, including marked. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
marked npm | From 1.1.1 | 2.0.0 |
marked npm | From 1.1.1 | 2.0.0 |
Products include Marked Project Marked.
How do I fix CVE-2021-21306?
Upgrade marked to 2.0.0 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2021-21306 being exploited?
There is no known exploitation of CVE-2021-21306 in the wild and no public exploit code.
Other vulnerabilities in markedjs marked
- CVE-2026-41680 Marked: OOM Denial of Service via Infinite Recursion in marked Tokenizer
- CVE-2017-16114 Regular Expression Denial of Service in marked
- CVE-2018-25110 Regular Expression Denial of Service (ReDoS) in markedjs/marked
- CVE-2014-3743 Multiple Content Injection Vulnerabilities in marked
- CVE-2016-10531 Sanitization bypass using HTML Entities in marked
Sources
Also known as GHSA-4r62-v4vq-hr96.