GHSA-h857-2g56-468g @mattkrick/sanitize-svg vulnerable to Cross-Site Scripting (XSS)

• npm @mattkrick/sanitize-svg: < 0.4.0 → fixed in 0.4.0

Impact The *sanitize-svg* package uses a deny-list-pattern to sanitize SVGs to prevent cross-site scripting (XSS). In doing so, literal ``-tags and on-event handlers were detected: ```typescript [...] const svgEl = div.firstElementChild! const attributes = Array.from(svgEl.attributes).map(({ name }) => name) const hasScriptAttr = !!attributes.find((attr) => attr.startsWith('on')) const scripts = svgEl.getElementsByTagName('script') return scripts.length === 0 && !hasScriptAttr ? svg : null [...] ``` There are more ways to embed JavaScript in XML files. Anchor Tag (requires user to click link): ```xml Lauritz ``` Foreign Object Tag (no user interaction required): ```xml Lauritz ``` As a result, downstream software that relies on `sanitize-svg` and expects resulting SVGs to be safe, may be vulnerable to XSS. We are aware of at least one downstream project for which this vulnerability had security implications. Patches This vulnerability was addressed in v0.4.0. Workarounds N/A