CVE-2024-45047: svelte XSS — Exploit

Description

svelte performance oriented web framework. A potential mXSS vulnerability exists in Svelte for versions up to but not including 4.2.19. Svelte improperly escapes HTML on server-side rendering. 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, and a type of the XSS is known as mXSS (mutation XSS). More specifically, this can occur when injecting malicious content into an attribute within a `noscript` tag. This issue has been addressed in release version 4.2.19. Users are advised to upgrade. There are no known workarounds for this vulnerability.

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CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
svelte	svelte	< 4.2.19

References

Exploits

https://github.com/sveltejs/svelte/security/advisories/GHSA-8266-84wp-wv5c

Frequently Asked Questions

What is CVE-2024-45047? +

svelte performance oriented web framework. A potential mXSS vulnerability exists in Svelte for versions up to but not including 4.2.19. Svelte improperly escapes HTML on server-side rendering. 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, and a type of the XSS is known as mXSS (mutation XSS). More specifically, this can occur when injecting malicious content into an attribute within a `noscript` tag. This issue has been addressed in release version 4.2.19. Users are advised to upgrade. There are no known workarounds for this vulnerability. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2024-45047? +

CVE-2024-45047 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-45047? +

CVE-2024-45047 affects products from svelte, specifically: svelte. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-45047? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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