CVE-2026-73490: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in flavorjones loofah
Loofah versions prior to 2.25.2 have a cross-site scripting vulnerability due to improper sanitization of SVG href attributes. The sanitizer only restricts xlink:href but browsers also accept href, allowing crafted SVGs to reference same-origin external documents that may contain malicious scripts or tracking images. This issue is fixed in version 2.25.2.
AI Analysis
Technical Summary
Loofah is an HTML/XML manipulation library built on Nokogiri. Before version 2.25.2, its HTML5 sanitizer applies local-reference restrictions only to the xlink:href attribute on SVG use and feImage elements, but browsers also accept the plain href attribute. This discrepancy allows a crafted sanitized SVG to reference arbitrary same-origin external documents, potentially rendering external SVG content with scripts or loading external images for tracking. Applications sanitizing user-supplied SVG with Loofah's default allowlist are affected. The vulnerability is addressed in version 2.25.2.
Potential Impact
An attacker can craft SVG content that bypasses the sanitizer's restrictions and references same-origin external documents containing malicious scripts or tracking images. This can lead to cross-site scripting (XSS) attacks with limited impact on confidentiality and integrity, and no impact on availability, as indicated by the CVSS vector. The vulnerability requires user interaction and has a high attack complexity.
Mitigation Recommendations
Upgrade Loofah to version 2.25.2 or later, where this issue is fixed. No other official remediation or temporary fixes are documented. Patch status is not yet confirmed by a vendor advisory, but the fix version is explicitly stated.
CVE-2026-73490: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in flavorjones loofah
Description
Loofah versions prior to 2.25.2 have a cross-site scripting vulnerability due to improper sanitization of SVG href attributes. The sanitizer only restricts xlink:href but browsers also accept href, allowing crafted SVGs to reference same-origin external documents that may contain malicious scripts or tracking images. This issue is fixed in version 2.25.2.
CVSS v3.1
Score 4.7medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Loofah is an HTML/XML manipulation library built on Nokogiri. Before version 2.25.2, its HTML5 sanitizer applies local-reference restrictions only to the xlink:href attribute on SVG use and feImage elements, but browsers also accept the plain href attribute. This discrepancy allows a crafted sanitized SVG to reference arbitrary same-origin external documents, potentially rendering external SVG content with scripts or loading external images for tracking. Applications sanitizing user-supplied SVG with Loofah's default allowlist are affected. The vulnerability is addressed in version 2.25.2.
Potential Impact
An attacker can craft SVG content that bypasses the sanitizer's restrictions and references same-origin external documents containing malicious scripts or tracking images. This can lead to cross-site scripting (XSS) attacks with limited impact on confidentiality and integrity, and no impact on availability, as indicated by the CVSS vector. The vulnerability requires user interaction and has a high attack complexity.
Mitigation Recommendations
Upgrade Loofah to version 2.25.2 or later, where this issue is fixed. No other official remediation or temporary fixes are documented. Patch status is not yet confirmed by a vendor advisory, but the fix version is explicitly stated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-08-12T19:00:33.735Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a7ce1eabf8831d5392b035b
Added to database: 08/12/2026, 21:13:14 UTC
Last enriched: 08/12/2026, 21:27:39 UTC
Last updated: 08/13/2026, 01:32:47 UTC
Views: 5
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