Svelte Vulnerable to XSS via DOM Clobbering of Internal Framework State (CVE-2026-42573) | HOL Guard CVE

Medium · CVSS 6.1CVE-2026-42573GHSA-RCQX-6Q8C-2C42

Svelte Vulnerable to XSS via DOM Clobbering of Internal Framework State

Answer in brief

CVE-2026-42573 records a Medium severity (CVSS 6.1) vulnerability in Svelte Vulnerable to XSS via DOM Clobbering of Internal Framework State. The current sources do not mark it as known exploited. The current feed maps svelte (npm). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published May 14, 2026Updated Jul 15, 2026Source checked Sep 17, 2026First seen by HOL Jun 11, 2026Material review Jul 15, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.1
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 6.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps svelte (npm). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
sveltenpm	<=5.55.6	5.55.7

Recommended response

Check inventory. Check lockfiles and deployed manifests for svelte.
Review the reported fix. Update svelte to 5.55.7 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
May 14, 2026
Evidence: source:ghsa:source_dates:source-dates:record
Source modified
Jul 15, 2026
Evidence: source:ghsa:source_dates:source-dates:record
First seen by HOL
Jun 11, 2026

Sources and claim methodology

Upstream source description

Svelte was vulnerable to DOM clobbering of its internal framework state on elements, potentially leading to XSS attacks. You are vulnerable if all of the following is true: - you are using attribute spreading on a form element - you are using attribute spreading or allow a dynamic value for the `name` attribute on an input or button element within that form - both of these are simultaneously user-controllable ```svelte <form {...spread1}> <input {...spread2}> </form> ```

Quoted source text, attributed separately from HOL analysis.