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CVE-2026-128120 SvelteKit: DoS while parsing form data from a remote functions `form`

7.5 high

High (7.5) in sveltejs kit.

On this page
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From version 2.42.0 until 3.1.1, applications using the experimental remote functions flag and a remote form function could perform quadratic synchronous work while parsing a specially crafted request with many form entries. The parsing work could block the event loop for an extended period and deny service. This issue is fixed in 3.1.1.

Severity

CVSS 3.1

7.5 high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
CWE-407 Inefficient Algorithmic Complexity
Published
Modified
Assigned by
GitHub_M (CNA)
NVD analysis
Deferred: the NVD does not plan to analyze it
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
sveltejs kit>= 2.42.0, < 3.1.1

History

  1. The NVD deferred its analysis

Changes since this site first stored the record. The same for every record: /api/public/changes.

References

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