Svelte 3.16.0 introduces subtle yet impactful changes compared to its predecessor, version 3.15.0, making it a worthwhile upgrade for developers leveraging this cybernetically enhanced web app framework. While the core description remains the same, several under-the-hood dependency updates contribute to enhanced performance and stability.
Notably, code-red progresses from version 0.0.25 to 0.0.26, and estree-walker jumps from 0.8.1 to 1.0.0. These updates likely involve bug fixes and potential performance improvements within Svelte's compilation process. While not immediately visible to the end-user, they contribute to a more robust and efficient development experience. The distribution details also show a slight difference. Version 3.16.0 has 207 files in the packaged tarball with an unpacked size of 3028091 bytes, while version 3.15.0 contains 252 files and an unpacked size of 3032082 bytes. Finally, it's important to note that version 3.16.0 was released later, incorporating any interim fixes or optimizations discovered since the 3.15.0 release. This incremental update approach ensures developers are consistently using the most refined version of the framework.
By staying current with the latest minor versions, developers benefit from cumulative enhancements, ensuring a smoother and more reliable development process when building modern web applications with Svelte.
All the vulnerabilities related to the version 3.16.0 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