SvelteKit Request Handling Vulnerabilities

Request body size limit bypass in SvelteKit adapter-node allows unauthenticated attackers to submit oversized payloads, causing denial of service through resource exhaustion. Affects SvelteKit versions prior to 2.57.1 running adapter-node. Exploitation requires specific timing conditions (CVSS AT:P). Platform-level and WAF body size limits remain effective. No public exploit identified at time of analysis. Vulnerability exploits CWE-770 resource allocation flaw where BODY_SIZE_LIMIT enforcement fails under race conditions or specific request patterns.

SvelteKit versions prior to 2.57.1 are vulnerable to denial of service when the redirect() function is called from the handle server hook with HTTP header-invalid characters in the location parameter. An unauthenticated remote attacker can trigger an unhandled TypeError by supplying unsanitized user input to the redirect location, potentially causing application crashes on certain platforms. The vulnerability is fixed in version 2.57.1.