Svelte is a UI framework that efficiently compiles your code to highly optimized vanilla JavaScript at build time, leading to smaller bundle sizes and better runtime performance compared to traditional virtual DOM approaches. Version 1.6.1, released on December 24, 2016, is a minor patch update to the previous stable version 1.6.0, released just a few days earlier on December 21, 2016. Examining the provided package data, the core functionalities and dependencies remain largely consistent between the two versions, with both relying on magic-string for source code manipulation. The development dependencies, which are crucial for building and testing the framework itself, also remain identical, including tools like rollup for bundling, eslint for linting, mocha for testing, and various Babel plugins for code transformation. This suggests that the changes introduced in version 1.6.1 likely address bug fixes or small improvements rather than significant feature additions.
For developers using Svelte, this means that upgrading from 1.6.0 to 1.6.1 should be a seamless process with minimal risk of breaking changes. While the specifics of the fixes are not detailed in the provided data, migrating to the newer version would ensure that you are using the most stable and refined version of the framework at that time. The consistent dependency list also reassures developers that the build and development process remains unchanged, allowing them to continue using their existing tooling and workflows without interruption. As always, checking the official Svelte changelog or release notes would provide more detailed information on the specific changes included in the patch.
All the vulnerabilities related to the version 1.6.1 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