Svelte is a UI framework that takes a unique 'disappearing' approach, compiling your code to highly efficient vanilla JavaScript at build time rather than doing the work in the browser. Versions 1.18.0 and 1.18.1 are remarkably similar, sharing the same core development dependencies which indicates consistent tooling and a stable development environment. These dependencies include tools like Rollup for bundling, Babel for JavaScript transpilation, ESLint for code linting, and various Babel plugins ensuring compatibility and optimized code transformation.
The primary difference lies in their release dates. Version 1.18.1 was published shortly after 1.18.0, suggesting it's likely a patch release addressing minor bugs or incorporating small improvements found after the initial 1.18.0 release. For developers, this means upgrading from 1.18.0 to 1.18.1 is generally advised to benefit from these fixes. Both versions offer a streamlined development experience, boasting tools that enhance code quality and project setup. Svelte's approach of shifting workload from the browser to the compilation, leading to faster and more performant applications. Also, the MIT license makes it a very versatile option for a wide range of projects.
All the vulnerabilities related to the version 1.18.1 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