Svelte version 1.49.2 is a minor update to the "magical disappearing UI framework," following closely on the heels of version 1.49.1. Both versions share an identical set of development dependencies, indicating that the core tooling and build process remained consistent between these releases. Developers already familiar with Svelte 1.49.1 won't encounter any changes in the developer experience regarding tooling or build setups when upgrading to 1.49.2.
The key difference lies in the release date. Version 1.49.2 was published on December 24, 2017, approximately a week after version 1.49.1, which was released on December 16, 2017. This suggests that version 1.49.2 likely contains bug fixes, performance improvements, or other minor enhancements that warranted a quick follow-up release.
For developers considering Svelte at this version, while the underlying framework remains the same, opting for 1.49.2 is advisable. Although the specific changes aren't explicitly detailed in this data, upgrading is considered a best practice to take advantage of any stability or performance benefits the newer version provides. Svelte, known for its compiler-first approach, aims to provide performant and efficient UI rendering, and staying up-to-date with minor versions helps ensure developers are leveraging the latest optimizations. This rapid iteration indicates an active development cycle focused on continuous improvement.
All the vulnerabilities related to the version 1.49.2 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