CVE-2020-26237

Published Nov 24, 2020

Last updated 2 years ago

Overview

Description
Highlight.js is a syntax highlighter written in JavaScript. Highlight.js versions before 9.18.2 and 10.1.2 are vulnerable to Prototype Pollution. A malicious HTML code block can be crafted that will result in prototype pollution of the base object's prototype during highlighting. If you allow users to insert custom HTML code blocks into your page/app via parsing Markdown code blocks (or similar) and do not filter the language names the user can provide you may be vulnerable. The pollution should just be harmless data but this can cause problems for applications not expecting these properties to exist and can result in strange behavior or application crashes, i.e. a potential DOS vector. If your website or application does not render user provided data it should be unaffected. Versions 9.18.2 and 10.1.2 and newer include fixes for this vulnerability. If you are using version 7 or 8 you are encouraged to upgrade to a newer release.
Source
security-advisories@github.com
NVD status
Analyzed

Risk scores

CVSS 3.1

Type
Primary
Base score
8.7
Impact score
5.8
Exploitability score
2.3
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:H
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
4.9
Impact score
4.9
Exploitability score
6.8
Vector string
AV:N/AC:M/Au:S/C:N/I:P/A:P

Weaknesses

security-advisories@github.com
CWE-471

Social media

Hype score
Not currently trending

Configurations