Vulnerabilidades de Fabricjs

Fabric.js is a Javascript HTML5 canvas library. Prior to 7.4.0, a potential Cross-Site Scripting (XSS) vulnerability exists in Fabric.js due to improper escaping of user-controlled input during SVG serialization via the toSVG() method. Specifically, the color field within the colorStops array of a fabric.Gradient object is not properly escaped when converted into SVG <stop> elements. If an application renders the generated SVG string into the DOM, this may allow an attacker to inject arbitrary HTML/SVG and execute JavaScript in the victim's browser. This vulnerability is fixed in 7.4.0.

Fabric.js is a Javascript HTML5 canvas library. Prior to version 7.2.0, Fabric.js applies `escapeXml()` to text content during SVG export (`src/shapes/Text/TextSVGExportMixin.ts:186`) but fails to apply it to other user-controlled string values that are interpolated into SVG attribute markup. When attacker-controlled JSON is loaded via `loadFromJSON()` and later exported via `toSVG()`, the unescaped values break out of XML attributes and inject arbitrary SVG elements including event handlers. Any application that accepts user-supplied JSON (via `loadFromJSON()`, collaborative sharing, import features, CMS plugins) and renders the `toSVG()` output in a browser context (SVG preview, export download rendered in-page, email template, embed) is vulnerable to stored XSS. An attacker can execute arbitrary JavaScript in the victim's browser session. Version 7.2.0 contains a fix.