CVE-2026-5160

Publication date 15 April 2026

Last updated 10 July 2026

Ubuntu priority

Cvss 3 Severity Score

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&colon;alert(1) is not recognized as dangerous during validation, leading to arbitrary script execution in the context of applications that render the URL.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
golang-github-yuin-goldmark	26.04 LTS resolute	Needs evaluation
	25.10 questing	Ignored end of life, was needs-triage
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Needs evaluation
	20.04 LTS focal	Needs evaluation

Severity score breakdown

CVSS version:

Base score 5.1 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Attack requirements	None
Privileges required	None
User interaction	Active
Vulnerable system - Confidentiality impact	None
Vulnerable system - Integrity impact	Low
Vulnerable system - Availability impact	None
Subsequent system - Confidentiality impact	Low
Subsequent system - Integrity impact	Low
Subsequent system - Availability impact	None

Scores

Parameter	Value
Base score	5.1 · Medium
Base + Threat score	-
Base + Environmental score	-
Base + Threat + Environmental score	-

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N

Base score 6.1 · Medium