Svelte version 1.56.1 is a patch release following closely after 1.56.0, both iterations of the "magical disappearing UI framework." Analyzing the metadata, the core difference lies in the bug fixes and minor improvements incorporated into the newer version. Both versions share identical development dependencies, indicating no changes in the tooling or build process. Developers relying on these tools (like Rollup, Typescript, eslint, prettier and others) for their Svelte projects can upgrade without worrying about compatibility issues with their existing setup, as the core dev infrastructure remains constant.
The dist object reveals that version 1.56.1 has a slightly larger unpackedSize (2302953 bytes) compared to 1.56.0 (2302458 bytes), perhaps hinting at code adjustments which explains the patch version update. While seemingly small, this size difference signifies internal improvements or targeted bug resolutions. Given the rapid succession of releases (less than two weeks apart), users are encouraged to update to version 1.56.1 to benefit from the latest fixes. Consider this update to iron out potential edge cases and further stabilize your Svelte applications. Released on March 5, 2018, it is the newest patch on the 1.56 version of the svelte library.
All the vulnerabilities related to the version 1.56.1 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