Svelte version 1.49.3 is a minor release following 1.49.2, both maintaining the core principles of the "magical disappearing UI framework." Examining the package.json data reveals no changes in the devDependencies section between these two versions. This suggests that the update likely focuses on bug fixes, performance improvements, or small tweaks to the existing functionality rather than introducing new features or altering the development dependencies.
For developers using Svelte, this means that upgrading from 1.49.2 to 1.49.3 should be a smooth process without requiring any modifications to their build setup or development environment. The key consideration revolves around any potential bug fixes addressed in 1.49.3. Reviewing the official Svelte changelog or release notes associated with this specific version is crucial to understand the exact nature of the changes.
Given the release dates, a mere four hours separate the publication of the two versions. This rapid succession often indicates a hotfix scenario—where a critical bug or issue was identified in 1.49.2 shortly after its release, necessitating a swift follow-up with 1.49.3. Therefore, staying informed about the specific fixes introduced in 1.49.3 will help developers decide if the update is essential for their projects, especially if they encountered any issues with the previous iteration. Essentially, it's a smaller update that warrants attention due to the speed with which it came out after the previous one.
All the vulnerabilities related to the version 1.49.3 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