CVE-2025-66564 Sigstore Timestamp Authority allocates excessive memory during request parsing

Sigstore Timestamp Authority is a service for issuing RFC 3161 timestamps. Prior to 2.0.3, Function api.ParseJSONRequest currently splits via a call to strings.Split an optionally-provided OID which is untrusted data on periods. Similarly, function api.getContentType splits the Content-Type heade...