Svelte version 2.4.4 is a minor update to the popular "magical disappearing UI framework," building upon the foundation laid by version 2.4.3. Both versions share the same core philosophy of compiling components to highly efficient vanilla JavaScript at build time, resulting in blazing-fast performance and a small bundle size for web applications. The description and the development dependencies appear to be identical between the two versions, indicating that the core functionality and the toolchain used for development remained consistent.
The key differences between versions 2.4.3 and 2.4.4 lie in the potential bug fixes, performance improvements, or minor feature enhancements that are not reflected in the package metadata. Developers upgrading from 2.4.3 to 2.4.4 can likely expect a smoother and more refined experience. The unpacked size increased slightly, from 2550836 bytes in v2.4.3 to 2552736 bytes in v2.4.4, pointing towards small augmentations to the code. The release date also indicates a very rapid release cycle, with version 2.4.4 deployed merely hours after 2.4.3. For developers using Svelte, both versions offer a component-based approach to building user interfaces, emphasizing reactivity and ease of use. The framework's ability to generate optimized JavaScript code makes it a compelling choice for projects where performance is critical. To understand the real differences it will be necessary to check the changelog on the official website or the release notes on Github.
All the vulnerabilities related to the version 2.4.4 of the package
Svelte vulnerable to XSS when using objects during server-side rendering
The package svelte before 3.49.0 is vulnerable to Cross-site Scripting (XSS) due to improper input sanitization and to improper escape of attributes when using objects during SSR (Server-Side Rendering). Exploiting this vulnerability is possible via objects with a custom toString() function.
Svelte has a potential mXSS vulnerability due to improper HTML escaping
A potential XSS vulnerability exists in Svelte for versions prior to 4.2.19.
Svelte improperly escapes HTML on server-side rendering. It converts strings according to the following rules:
" -> "& -> &< -> <& -> &The assumption is that attributes will always stay as such, but in some situation the final DOM tree rendered on browsers is different from what Svelte expects on server-side rendering. This may be leveraged to perform XSS attacks. More specifically, this can occur when injecting malicious content into an attribute within a <noscript> tag.
A vulnerable page (+page.svelte):
<script>
import { page } from "$app/stores"
// user input
let href = $page.url.searchParams.get("href") ?? "https://example.com";
</script>
<noscript>
<a href={href}>test</a>
</noscript>
If a user accesses the following URL,
http://localhost:4173/?href=</noscript><script>alert(123)</script>
then, alert(123) will be executed.
XSS, when using an attribute within a noscript tag