CVE-2026-5160

Severity CVSS v4.0:
MEDIUM
Type:
CWE-79 Cross-Site Scripting (XSS)
Publication date:
15/04/2026
Last modified:
15/04/2026

Description

Versions of the package github.com/yuin/goldmark/renderer/html before 1.7.17 are vulnerable to Cross-site Scripting (XSS) due to improper ordering of URL validation and normalization. The renderer validates link destinations using a prefix-based check (IsDangerousURL) before resolving HTML entities. This allows an attacker to bypass protocol filtering by encoding dangerous schemes using HTML5 named character references. For example, a payload such as javascript:alert(1) is not recognized as dangerous during validation, leading to arbitrary script execution in the context of applications that render the URL.