# CVE-2018-20801: Highcharts regular expression denial of service

Source: https://junglewise.ai/threats/cve-2018-20801-highcharts-regular-expression-denial-of-service  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2019-03-18. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2018-20801 · Severity: low · CVSS 3 · Published 2019-03-18

Highcharts is a widely-used JavaScript charting library used to create interactive graphs and visualizations in web applications. Versions before 6.1.0 contain a regular expression parsing flaw that allows untrusted input to cause excessive processing, rendering the application unresponsive and disrupting service availability for users.

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

## Quick answers

**Is CVE-2018-20801 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2018-20801 being exploited in the wild.

**How severe is CVE-2018-20801?** Low severity, with a CVSS score of 3, published 18 March 2019.

**Which products and versions are affected?** highcharts (npm) SEMVER:introduced=0,fixed=6.1.0.

**Is there a fix for CVE-2018-20801?** Yes. highcharts (npm): upgrade to 6.1.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2018-20801 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2018-20801?** Check whether you run highcharts (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

- highcharts (npm): upgrade to 6.1.0 or later

  ```sh
  npm install highcharts@6.1.0
  ```


## Technical details

This vulnerability is a Regular Expression Denial of Service (ReDoS) affecting the SVGRenderer text processing component in Highcharts. Untrusted input passed to text rendering functions can trigger catastrophic backtracking in poorly-designed regular expressions used to parse and replace attributes such as class, href, and style. The attack requires only network reachability with no authentication needed, and exploiting it causes the application to consume excessive CPU and become unresponsive. The vulnerability was patched in version 6.1.0 by refactoring the regex patterns to avoid backtracking-prone constructs.

## Affected products

- Highcharts Highcharts < 6.1.0

## Identifiers

- CVE-2018-20801
- GHSA-xmc8-cjfr-phx3

## Timeline

- 2019-03-18: disclosed
- 2018-03-01: patched: Fix commit authored, patch released in version 6.1.0

## References

- [https://github.com/highcharts/highcharts/commit/7c547e1e0f5e4379f94396efd559a566668c0dfa](https://github.com/highcharts/highcharts/commit/7c547e1e0f5e4379f94396efd559a566668c0dfa)

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