SvelteKit versions from 2.49.0 through 2.53.2 (fixed in 2.53.3) contain a deserialization expansion issue in the experimental form remote function. When an application enables experimental.remoteFunctions and uses the form function to process the files array without validating files.length or individual file sizes, an attacker can submit relatively small inputs that expand into very large file arrays, leading to expensive processing and denial of service.

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Fri, 28 Aug 2026 11:30:00 +0000

Type Values Removed Values Added
Description SvelteKit versions from 2.49.0 through 2.53.2 (fixed in 2.53.3) contain a deserialization expansion issue in the experimental form remote function. When an application enables experimental.remoteFunctions and uses the form function to process the files array without validating files.length or individual file sizes, an attacker can submit relatively small inputs that expand into very large file arrays, leading to expensive processing and denial of service.
Title SvelteKit 2.49.0 before 2.53.3 Denial of Service via form
First Time appeared Svelte
Svelte kit
Weaknesses CWE-502
CPEs cpe:2.3:a:svelte:kit:*:*:*:*:*:*:*:*
Vendors & Products Svelte
Svelte kit
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-08-28T10:49:42.969Z

Reserved: 2026-08-28T10:39:30.356Z

Link: CVE-2026-82259

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-28T12:16:38.953

Modified: 2026-08-28T12:16:38.953

Link: CVE-2026-82259

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses