Svelte version 1.3.0 represents a subtle but important evolution of the "magical disappearing UI framework" compared to its predecessor, version 1.2.5. While both versions share the same core dependencies, relying on magic-string for string manipulation, a key utility within Svelte's compilation process, the update signifies a refinement of the underlying tooling and build pipeline. For developers already using Svelte, transitioning to 1.3.0 should be seamless, as the core API and component structure remain consistent.
The real story lies in the potential behind-the-scenes improvements. Although the devDependencies largely mirror each other, indicating stability in the testing and build environment, every seemingly small update to a library represents a potential for enhanced performance, bug fixes, and improved compatibility with the ever-evolving JavaScript ecosystem. The unchanged devDependencies list suggests a confident continuation of the existing development workflow, relying on tools like rollup for bundling, eslint for code quality, and mocha for testing.
Ultimately, while the differences aren't immediately apparent from a superficial comparison, users can expect a more polished and reliable experience. Given that even point releases often include crucial optimizations and error corrections, upgrading to Svelte 1.3.0 ensures you're working with the most current iteration of the framework. The release date difference of just two days suggests this was likely a patch addressing urgent needs identified after the 1.2.5 release.
All the vulnerabilities related to the version 1.3.0 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