svg-sanitizer vulnerabilities

svg-sanitizer from 0.11.0 before 1.1.0 contains an uncaught exception vulnerability that allows attackers to crash callers by submitting well-formed XML without a top-level svg root. Attackers can supply documents with a non-svg root or nested svg element, causing Sanitizer::sanitize() to throw a LogicException instead of returning false, crashing workers or bypassing upload rejection.

svg-sanitizer from 0.5.3 before 1.1.0 contains a denial of service vulnerability in Sanitizer::sanitize() that repeatedly rescans the whole input while stripping PHP tags. Unauthenticated attackers can upload SVGs with many overlapping PHP tag openers and closers, forcing quadratic preg_replace passes that exhaust worker CPU for minutes.

darylldoyle svg-sanitizer before 1.0.0 contains CSS injection and remote reference bypass vulnerabilities that allow attackers to embed external resources by uploading crafted SVG files. Attackers can use unsanitized style content, unquoted url() values, or image href attributes to exfiltrate page data, track users, or disclose visitor IP addresses.

svg-sanitizer is a PHP SVG/XML sanitizer. Prior to 1.0.0, Resolver::processReferences() in src/ElementReference/Resolver.php builds the SVG <use> reference graph with a case-sensitive href attribute predicate before cleanHrefAttributes() normalizes mixed-case names. An attacker can provide xlink:HrEf on nested <use> elements so the graph omits those references, after which the sanitizer converts the attribute to canonical xlink:href and returns the live nesting structure without applying the useNestingLimit protection. A consuming application that renders the sanitized SVG can therefore be exposed to the resource exhaustion that control is designed to prevent. This issue is fixed in version 1.0.0.