Dear Readers,
today we want to share a method on how to test an OCSP over HTTP validation service with Burp and some Python magic. First a little background about OCSP (Online Certificate Status Protocol): the main purpose of OCSP is to validate the status of an X.509 certificate.
The OCSP responder is the key part of the system. It is run by the certificate authority and responds with one of three possible different answers. The first one is “good”, which indicates that the certificate is not banned, “revoked” means that the certificate is banned, and “unknown” simply says that the status could not be determined, because the issuing CA of the Cert is not known to the responder.
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