Svelte version 3.6.7 arrived on July 10, 2019, shortly after version 3.6.6 released on July 9, 2019, illustrating Svelte's active development cycle. Both versions maintain the description "Cybernetically enhanced web apps," hinting at their ambition to offer a cutting-edge development experience. Examining the package.json files reveals a virtually identical dependency structure, sharing a comprehensive suite of development tools. Key dependencies include Rollup for bundling, Typescript for enhanced type safety, and ESLint for code linting, ensuring a robust and maintainable codebase.
While the core dependencies remain consistent, subtle variations within the dist object signal underlying improvements. Version 3.6.7 has one less file and a slightly bigger unpacked size. This suggests optimizations or minor adjustments related to build artifacts or distribution, likely impacting performance or compatibility in specific scenarios. For developers, this highlights the importance of staying updated to leverage these incremental enhancements. This continuous refinement underscores Svelte's commitment to providing a stable yet evolving framework for building high-performance web applications. Choosing the latest version will generally ensure you have the latest fixes and optimizations that can result in better overall characteristics of your application.
All the vulnerabilities related to the version 3.6.7 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