{"id":"CVE-2026-86251","state":"PUBLISHED","title":"h3 before 1.15.9 Path Traversal via Double Decoding","description":"h3 versions before 1.15.9 contain a path traversal vulnerability in the serveStatic utility. A double-decoding flaw allows a request path containing double-encoded dot sequences (e.g. %252e%252e) to be decoded to %2e%2e, which survives resolveDotSegments() because that function only checks for literal '.' characters. 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