Svelte 3.22.3 is a minor version update to the popular Svelte JavaScript framework, building upon the solid foundation of version 3.22.2. Both versions share the same core mission: crafting "cybernetically enhanced web apps," emphasizing performance and a streamlined developer experience. Examining the devDependencies object reveals that essentially, no direct dependency versions have changed between these releases, indicating that the update focuses primarily on internal improvements, bug fixes, and refinements rather than introducing breaking API changes or substantial new features that would necessitate dependency updates. A key difference can be noticed in the dist object. Svelte 3.22.3 sees a change in file count, an increase from 204 to 205, suggesting the addition of at least one new file. The unpackedSize decreases from 3,134,435 bytes in 3.22.2 to 3,121,827 bytes in 3.22.3, meaning a possible optimisation or refactor impacting final project size. The difference in releaseDate confirms that 3.22.3 was released later.
For developers, this means that upgrading from 3.22.2 to 3.22.3 should be a smooth and relatively risk-free process. Given the lack of dependency changes, updating promises incremental improvements and bug fixes without the overhead of dealing with potentially breaking changes in underlying tools. Before upgrading any Svelte project, developers should check the changelog or release notes for 3.22.3 on the official Svelte website or GitHub repository to be aware of the exact issues addressed.
All the vulnerabilities related to the version 3.22.3 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