cf.tls_client_auth.cert_issuer_serial
cf.tls_client_auth.cert_issuer_serial String Serial number of the direct issuer of the certificate in the request.
This field is only filled in if the request includes a client certificate for mTLS authentication.
Example value:
"2688201DBA77402EA87118876F2E1B24CF8B0395" Categories: 
   - Request
 - mTLS
 
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