Plate media plugins has a XSS in media embed element when using custom URL parsers

### Impact Editors that use `MediaEmbedElement` and pass custom `urlParsers` to the `useMediaState` hook may be vulnerable to XSS if a custom parser allows `javascript:`, `data:` or `vbscript:` URLs to be embedded. Editors that do not use `urlParsers` and instead consume the `url` property directly may also be vulnerable if the URL is not sanitised. The default parsers `parseTwitterUrl` and `parseVideoUrl` are not affected. Examples of vulnerable code: ```tsx const { embed } = useMediaState({ urlParsers: [ // Custom parser that does not use an allowlist or validate the URL protocol (url) => ({ url }), ], }); return ( <iframe src={embed!.url} // ... /> ); ``` ```tsx const { url } = useMediaState(); return ( <iframe // url property used directly from useMediaState() with no sanitisation src={url} // ... /> ); ``` ```tsx const { url } = element; return ( <iframe // url property used directly from element with no sanitisation src={url} // ... /> ); ``` ### Patches `@udecode/plate-media` 36.0.10 resolves this issue by only allowing HTTP and HTTPS URLs during parsing. This affects only the `embed` property returned from `useMediaState`. In addition, the `url` property returned from `useMediaState` has been renamed to `unsafeUrl` to indicate that it has not been sanitised. The `url` property on `element` is also unsafe, but has not been renamed. If you're using either of these properties directly, you will still need to validate the URL yourself. ### Workarounds Ensure that any custom `urlParsers` do not allow `javascript:`, `data:` or `vbscript:` URLs to be returned in the `url` property of their return values. If `url` is consumed directly, validate the URL protocol before passing it to the `iframe` element. ### References How to verify the protocol of a URL: https://stackoverflow.com/a/43467144

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