Improper Encoding or Escaping of Output Affecting justhtml package, versions [0.9.0,1.22.0)
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Test your applications- Snyk IDSNYK-PYTHON-JUSTHTML-17670531
- published29 Jun 2026
- disclosed25 Jun 2026
- creditUnknown
Introduced: 25 Jun 2026
New CVE NOT AVAILABLE CWE-116 (opens in a new tab)Common Weakness Enumeration (CWE) is a category system for software weaknesses
Common Weakness Enumeration (CWE) is a category system for software weaknesses
How to fix?
Upgrade justhtml to version 1.22.0 or higher.
Overview
justhtml is an A pure Python HTML5 parser that just works.
Affected versions of this package are vulnerable to Improper Encoding or Escaping of Output in the to_markdown process. An attacker can inject malicious HTML or script into rendered Markdown by including a blank line within the text of a <code> element or a <pre> element inside a link, causing unescaped content to be interpreted as live HTML or Markdown when viewed by another user.