# CVE-2019-12041: remarkable Regular Expression Denial of Service via CDATA

Source: https://junglewise.ai/threats/cve-2019-12041-remarkable-regular-expression-denial-of-service-via-cdata  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2019-06-06. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2019-12041 · Severity: low · CVSS 3.1 · Published 2019-06-06

Remarkable is a popular Markdown parser library used to convert Markdown text into HTML. A flaw in its HTML tag parsing logic allows an attacker to cause the parser to hang indefinitely by submitting specially crafted input containing a malformed CDATA section, resulting in service unavailability for applications that depend on this library.

Technologies: [remarkable (npm)](https://junglewise.ai/threats/technologies/remarkable). Vendors: [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2019-12041 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2019-12041 being exploited in the wild.

**How severe is CVE-2019-12041?** Low severity, with a CVSS score of 3.1, published 6 June 2019.

**Which products and versions are affected?** remarkable (npm) SEMVER:introduced=0,fixed=1.7.2.

**Is there a fix for CVE-2019-12041?** Yes. remarkable (npm): upgrade to 1.7.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2019-12041 attacked?** It is attacked over the network.

**Am I affected by CVE-2019-12041?** Check whether you run remarkable (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- remarkable (npm): upgrade to 1.7.2 or later

  ```sh
  npm install remarkable@1.7.2
  ```


## Technical details

The vulnerability is a Regular Expression Denial of Service (ReDoS) condition in lib/common/html_re.js affecting versions prior to 1.7.2. The vulnerable regex pattern used to parse CDATA sections exhibits catastrophic backtracking when processing malformed input with repeating characters in the CDATA section. An attacker can trigger indefinite CPU consumption by providing input such as `<![CDATA[aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa]]>`, causing the application to hang. The attack requires only network access to an application that processes untrusted Markdown via Remarkable; no authentication or special privileges are needed. The fix was released in version 1.7.2.

## Affected products

- remarkable remarkable < 1.7.2

## Identifiers

- CVE-2019-12041
- GHSA-q22g-8fr4-qpj4

## Timeline

- 2019-05-13: disclosed
- 2019-06-06: advisory
- 2019: patched: Fix released in version 1.7.2

## References

- [https://github.com/jonschlinkert/remarkable/issues/331](https://github.com/jonschlinkert/remarkable/issues/331)

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- [remarkable content injection via unescaped javascript protocol](https://junglewise.ai/threats/cve-2014-10065-remarkable-content-injection-via-unescaped-javascript-protocol)
- [Remarkable Cross-site Scripting via unprintable characters in URLs](https://junglewise.ai/threats/cve-2019-12043-remarkable-cross-site-scripting-via-unprintable-characters-in)
- [remarkable XSS via data URI in links](https://junglewise.ai/threats/cve-2017-16006-remarkable-xss-via-data-uri-in-links)