NetSight
critical9.8

CVE-2026-7808

justhtml before 1.16.0 contains multiple HTML sanitization bypass issues that can allow active/dangerous content (e.g., script or style) to survive sanitizatio…

Impact

justhtml before 1.16.0 contains multiple HTML sanitization bypass issues that can allow active/dangerous content (e.g., script or style) to survive sanitization, potentially leading to cross-site scripting. The issues primarily affect advanced usage rather than the default JustHTML(..., sanitize=True) path for ordinary parsed HTML: mutating or reusing sanitization policy objects (including exported defaults) could weaken later sanitization; programmatic DOM input to sanitize()/sanitize_dom() could miss mixed-case tag names (e.g., ScRiPt, StYlE); crafted programmatic doctype names could serialize into active markup; and custom policies preserving SVG or MathML could allow animation elements, presentation attributes with external url(...) references, or DOM trees mislabeled as namespace="html" to bypass foreign-content checks. Fixed in 1.16.0.

Affected products

ProductAffected versions
Justhtml
before 1.16.0

Versions were read from the advisory text. No structured product data has been published for this record yet.

Weakness classification

References