CVE-2026-128117
SvelteKit: Unhandled URIError when `reroute` rewrites a malformed pathname crashes adapter-node
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to versions 2.70.4 and 3.1.1, the reroute hook could rewrite an invalid percent-encoded pathname into a valid route and reach a comparison that decoded the original malformed pathname outside the guarded decoding operation. The resulting unhandled URIError could crash an adapter-node server and deny service to other requests. This issue is fixed in 2.70.4 and 3.1.1.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| kit sveltejs |
< 2.70.4 (affected) >= 3.0.0, < 3.1.1 (affected) |
CNA: GitHub_M |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 5.9 medium |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA: GitHub_M |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/sveltejs/kit/security/advisories/GHSA-mw6w-2fmv-pvw3CNA: GitHub_M · x_refsource_CONFIRM
- https://github.com/sveltejs/kit/pull/17620CNA: GitHub_M · x_refsource_MISC
- https://github.com/sveltejs/kit/commit/0a2e58cbccdd46cac20aa5af4e2edf17e0da11ddCNA: GitHub_M · x_refsource_MISC
- https://github.com/sveltejs/kit/commit/7993d5ebab017cb1be898a0b1c57371c5da06557CNA: GitHub_M · x_refsource_MISC
- https://github.com/sveltejs/kit/releases/tag/@sveltejs/[email protected]CNA: GitHub_M · x_refsource_MISC
- https://github.com/sveltejs/kit/releases/tag/@sveltejs/[email protected]CNA: GitHub_M · x_refsource_MISC
For agents and automation
Read public disclosures for free as Markdown or JSON. Compatible browsers also expose native WebMCP tools to search disclosures, read this page, and discover API access.
Use the ontology-linked Cyber API with x402 pay per request, or a Y2 Pro or Elite API key with the intel:cyber scope.
Endpoints and access details
https://api.y2.dev/api/v2/cyber/cveshttps://api.y2.dev/api/v2/cyber/cves/{cveId}
A workspace owner or admin can create a Pro or Elite API key. Send Authorization: Bearer <Y2_API_KEY> from your trusted agent runtime.
For x402, omit Authorization and read the HTTP 402 payment challenge before signing a retry. Public browser tools do not make payments.