Infinite loop Affecting justhtml package, versions [,1.17.0)
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Test your applications- Snyk IDSNYK-PYTHON-JUSTHTML-16318347
- published28 Apr 2026
- disclosed22 Apr 2026
- creditUnknown
Introduced: 22 Apr 2026
New CVE NOT AVAILABLE CWE-436 (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
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 1.17.0 or higher.
Overview
justhtml is an A pure Python HTML5 parser that just works.
Affected versions of this package are vulnerable to Infinite loop via custom sanitization policies or programmatic DOM manipulation. An attacker can inject and execute arbitrary scripts, cause resource loading, or trigger external fetches by crafting malicious SVG, MathML, or CSS content that bypasses sanitization.
Note: This is only exploitable if custom policies preserve SVG, MathML, or