Svelte version 2.9.9 represents a minor version update from 2.9.8 in the ecosystem of this magical disappearing UI framework. Both versions share the same core description, emphasizing Svelte's approach to building user interfaces. Analyzing the package data, the primary difference lies in the "dist" section. Version 2.9.9 has a slightly larger unpacked size of 2604551 bytes compared to version 2.9.8's 2604457 bytes, denoting small adjustments or fixes within the compiled code. Crucially, the file count remains identical at 17, suggesting the additional bytes are within the existing files and not from new files introduced. Furthermore, the release date indicates that version 2.9.9 was published shortly after 2.9.8, reflecting rapid iteration or a quick fix.
For developers using Svelte, this minor increment most likely incorporates bug fixes, performance enhancements, or very subtle feature improvements that are backward compatible. While the dependency list remains identical, suggesting no changes to the tools required for development, users might benefit from upgrading to 2.9.9 for stability and minor usability improvements without expecting significant API alterations. Reviewing the changelog or release notes associated with these specific versions on the Svelte repository would reveal the precise nature of the updates.
All the vulnerabilities related to the version 2.9.9 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