CVE-2020-26237 : Vulnerability Insights and Analysis

Highlight.js versions before 9.18.2 and 10.1.2 are vulnerable to Prototype Pollution, allowing for potential DOS attacks.

Understanding CVE-2020-26237

Highlight.js, a JavaScript syntax highlighter, is susceptible to Prototype Pollution, impacting versions prior to 9.18.2 and 10.1.2.

What is CVE-2020-26237?

Highlight.js is a syntax highlighter in JavaScript vulnerable to Prototype Pollution.
Malicious HTML code blocks can lead to pollution of the base object's prototype, causing unexpected behavior.
Versions 9.18.2 and 10.1.2 onwards have fixes for this vulnerability.

The Impact of CVE-2020-26237

CVSS Score: 5.8 (Medium Severity)
Attack Complexity: High
Attack Vector: Network
Integrity Impact: High
User Interaction: Required
Scope: Changed
Privileges Required: Low
Potential DOS vector due to unexpected properties causing application crashes.

Technical Details of CVE-2020-26237

Highlight.js is vulnerable to Prototype Pollution, affecting specific versions.

Vulnerability Description

Malicious HTML code blocks can pollute the base object's prototype during highlighting.

Affected Systems and Versions

Products: highlight.js
Vendor: highlightjs
Vulnerable Versions: < 9.18.2, >= 10.0.0, < 10.1.2

Exploitation Mechanism

Crafted HTML code blocks can lead to prototype pollution, impacting application behavior.

Mitigation and Prevention

Steps to address and prevent the CVE-2020-26237 vulnerability.

Immediate Steps to Take

Update highlight.js to versions 9.18.2 or 10.1.2 and newer to mitigate the risk.
Avoid allowing users to insert custom HTML code blocks without proper filtering.

Long-Term Security Practices

Regularly update highlight.js to the latest secure versions.
Implement input validation and filtering to prevent malicious code injection.

Patching and Updates

Upgrade to highlight.js versions 9.18.2 or 10.1.2 and newer to address the Prototype Pollution vulnerability.