CVE-2026-128118 SvelteKit: Build-time server-only module import guard could fail, resulting in server secrets being statically replaced in client bundle
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From version 3.0.0 until 3.1.1, the build-time server-only module guard did not treat src/params.js as a client entry point even though parameter matchers can run in the browser. Server-only modules imported through src/params.js could consequently enter the client bundle, where statically replaced private environment values or other server secrets could be exposed. This issue is fixed in 3.1.1.
Severity
CVSS 3.1
7.5 high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CWEs
CWE-200Exposure of Sensitive Information to an Unauthorized Actor CWE-668Exposure of Resource to Wrong Sphere
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