CVE-2026-82259

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/sveltejs/kit/security/advisories/GHSA-fpg4-jhqr-589c	Vendor Advisory
https://www.vulncheck.com/advisories/sveltekit-2.49.0-before-2.53.3-denial-of-service-via-form	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:svelte:sveltekit:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-08-28 12:16

Updated : 2026-08-31 17:07

NVD link : CVE-2026-82259

Mitre link : CVE-2026-82259

CVE.ORG link : CVE-2026-82259

JSON object : View

Products Affected

svelte

sveltekit

CWE

CWE-502

Deserialization of Untrusted Data

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