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TI-2026-18320 Aliases CVE-2026-22803GHSA-j2f3-wq62-6q46

SvelteKit has a memory amplification DoS in Remote Functions binary form deserializer

Priority MEDIUM 42CWE-789Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-789.

Summary

SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From 2.49.0 to 2.49.4, the experimental form remote function uses a binary data format containing a representation of submitted form data. A specially-crafted payload can cause the server to allocate a large amount of memory, causing DoS via memory exhaustion. This vulnerability is fixed in 2.49.5.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00585 48th percentileScored 2026-11-07
Fix Fixed kit (sveltejs): 2.49.5@sveltejs/kit (npm): 2.49.5

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
sveltejskit2.49.0 to before 2.49.52.49.5Patch availableCNA
—@sveltejs/kit (npm)2.49.0 to before 2.49.52.49.5Patch availableGHSA-j2f3-wq62-6q46
  • kit Vendorsveltejs Affected 2.49.0 to before 2.49.5 Fixed in 2.49.5 Patch available CNA
  • @sveltejs/kit (npm) Vendor— Affected 2.49.0 to before 2.49.5 Fixed in 2.49.5 Patch available GHSA-j2f3-wq62-6q46

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:svelte:kit:*:*:*:*:*:node.js:*:*2.49.0 to before 2.49.5Vulnerablesveltejs
  • cpe:2.3:a:svelte:kit:*:*:*:*:*:node.js:*:* Versions 2.49.0 to before 2.49.5 Vulnerable ·sveltejs

Remediation

  • Fix · CNA kit (sveltejs) Fixed in 2.49.5
  • Fix · GHSA-j2f3-wq62-6q46 @sveltejs/kit (npm) Fixed in 2.49.5 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-22803
  2. 2026-10-03 Alias added: GHSA-j2f3-wq62-6q46

References

Patch 1

Advisory 2

Other 3

  • TI-2024-15660 Sending a GET or HEAD request with a body crashes SvelteKit CVSS 3.1HIGH 7.5
  • TI-2025-41390 SvelteKit Denial of service and possible SSRF when using prerendering CVSS 4.0HIGH 8.4
  • TI-2026-28904 SvelteKit has a BODY_SIZE_LIMIT bypass in @sveltejs/adapter-node CVSS 4.0HIGH 8.2
  • TI-2026-28905 SvelteKit's invalidated redirect in handle hook causes Denial-of-Service CVSS 4.0MEDIUM 6.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences