Svelte 3.45.0 represents a subtle but noteworthy update to the Svelte JavaScript framework, building upon the solid foundation of version 3.44.3. Both versions share the same core description: "Cybernetically enhanced web apps," highlighting Svelte's commitment to efficient and performant web development. A primary differentiator lies in the updated code-red dev dependency, moving from version 0.2.3 in 3.44.3 to 0.2.4 in the newer release. While seemingly minor, such updates often incorporate critical bug fixes or performance refinements within Svelte's compilation pipeline, which could have a positive impact on the generated code and potentially reduce bundle sizes.
The unpacked size also sees a minor increase in version 3.45.0, suggesting some additions or modifications to the core library or its tooling. Developers should consider this when aiming for minimal footprint in their applications. Moreover, the release date jump from December 2021 to January 2022 indicates a concentrated effort to address issues or introduce incremental improvements identified in the preceding weeks. Although not a major release packed with groundbreaking features, Svelte 3.45.0 delivers an optimized and refined developer experience, continuing the trend of iterative progress expected from a mature framework. Developers should upgrade for potential performance gains and bug fixes.
All the vulnerabilities related to the version 3.45.0 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