rails-html-sanitizer is responsible for sanitizing HTML fragments in Rails applications. From 1.0.3 until 1.7.1, Rails::HTML::PermitScrubber restricted SVG reference elements in SVG_ALLOW_LOCAL_HREF only when they used xlink:href, even though browsers also accept the plain href attribute. Applications with non-default allowed tags that included SVG use or feImage elements could therefore permit external references; a same-origin external SVG referenced by use could execute scripts in the sanitized document's context, while feImage could load external images for tracking. Applications using the default allowed tags are not affected. This issue is fixed in version 1.7.1.

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlAttributeSanitizer::getSupportedAttributes() omits URL-valued attributes including action, formaction, poster, and cite, so configurations that admit those attributes can leave javascript: URIs unsanitized and enable XSS when the resulting HTML is rendered or a victim submits a form or clicks a button. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0 until 6.4.41, 7.4.13, and 8.0.13, UrlAttributeSanitizer::getSupportedAttributes() omitted URL-bearing attributes on <object>, <applet>, <iframe>, and <img>, and <meta http-equiv="refresh"> URLs inside content bypassed URL sanitization, allowing explicitly enabled elements or attributes to pass javascript: and similar payloads into sanitized output. This issue is fixed in versions 6.4.41, 7.4.13, and 8.0.13.

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0 until 6.4.41, 7.4.13, and 8.0.13, UrlSanitizer::parse() rejected raw BiDi formatting characters but not percent-encoded forms and used an ASCII-only whitespace check, allowing sanitized URLs to retain visual-spoofing characters that downstream consumers could decode or display. This issue is fixed in versions 6.4.41, 7.4.13, and 8.0.13.

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlSanitizer::parse() passes Unicode explicit-direction BiDi formatting characters through into sanitized href and src attributes, allowing sanitized content to display a link destination that visually differs from the actual destination and enabling phishing-style visual spoofing. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, HtmlSanitizer URL sanitization can allow off-allowlist URLs through allowLinkHosts() or allowMediaHosts() because UrlSanitizer::parse() follows RFC 3986 while browsers follow WHATWG URL parsing, and because <area href> is checked against the media policy rather than the link policy. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.