[h3] h3: Double Decoding in `serveStatic` Bypasses `resolveDotSegments` Path Traversal Protection via `%252e%252e`

**[h3] h3: Double Decoding in `serveStatic` Bypasses `resolveDotSegments` Path Traversal Protection via `%252e%252e`**

Summary The serveStatic utility in h3 applies a redundant decodeURI() call to the request pathname after H3Event has already performed percent-decoding with %25 preservation. This double decoding converts %252e%252e into %2e%2e, which bypasses resolveDotSegments() (since it checks for literal . characters, not percent-encoded equivalents). When the resulting asset ID is resolved by URL-based backends (CDN, S3, object storage), %2e%2e is interpreted as .. per the URL Standard, enabling path traversal to read arbitrary files from the backend...

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