Cross-site Scripting (XSS) Affecting php-league-commonmark package, versions *


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.36% (27th percentile)

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  • Snyk IDSNYK-ECHOLATEST-PHPLEAGUECOMMONMARK-18612365
  • published11 Aug 2026
  • disclosed6 Aug 2026

Introduced: 6 Aug 2026

CVE-2026-71478  (opens in a new tab)
CWE-79  (opens in a new tab)
CWE-86  (opens in a new tab)
CWE-692  (opens in a new tab)

How to fix?

There is no fixed version for Echo:latest php-league-commonmark.

NVD Description

Note: Versions mentioned in the description apply only to the upstream php-league-commonmark package and not the php-league-commonmark package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

league/commonmark is a PHP library for parsing and rendering CommonMark Markdown. From 1.5.0 until 2.9.0, the AttributesExtension's href and src unsafe-link filter can be bypassed by embedding control bytes, such as a tab, carriage return, line feed, or leading C0 control character, in a javascript: URL that browsers discard before parsing the scheme, causing the browser to still execute the script even when the unsafe-link filter is enabled. This issue is fixed in 2.9.0.