Can certificate transparency detect SSL Pinning bypass in Mobile Applications?

Question

I was reading through Certificate Transparency (CT) and its capabilities to monitor use and abuse of certificates. I am wondering if CT can detect SSL Pinning bypass in Mobile application (in case of Web Application for that matter). Request you to enlighten me on this. If yes, how? if no, why?

Answer 1

TL;DR

CT can not detect bypass of SSL Pinning in your mobile applications

CT and SSL Pinning are two different things. In SSL Pinning you are ensuring that either certificate hash/public key hash received during TLS handshake matched with the one pinned within the application to ensure that you only trust a whitelisted certificate instead of trusting everything in the device trust store whereas through CT we perform cryptographic checks to ensure if we received a valid SCT(Signed Certificate Timestamp) and log server pushed the cert entries to a public append-only log so as to ensure that there is no rouge cert generated for our domains by malicious trusted CA or through the compromise of a CA.

Also, note that with CT we only ensure that the certificates issued by PUBLIC CAs were issued legitimately whereas while performing MITM to intercept app traffic/bypassing pinning we use the certificate of proxy server(Charles/Burp/ZAP) which is not a public CA and hence the checks are not enforced through CT