CVE-2026-82259

SvelteKit 2.49.0 before 2.53.3 Denial of Service via form

Published Aug 28, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Svelte sveltekit
CPEs cpe:2.3:a:svelte:sveltekit:*:*:*:*:*:node.js:*:*
Vendors & Products Svelte sveltekit
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Oct 8, 2026, 3:25 PM
Reserved
Aug 28, 2026, 10:39 AM
Status
Analyzed
Published
Aug 28, 2026, 12:16 PM
Modified
Oct 8, 2026, 4:17 PM