Avast blocks "rpt.cedexis.com"

[REDACTED]

My Avast is making a window pop up in the bottom right corner of my screen everytime I visit tumblr.com and everytime I either refresh it or click "next page" (since I have endless scrolling disabled). I don't know what rpt.cedexis is, don't know what to do and it's very annoying... The message it gives me says "Avast has blocked access to https://rpt.cedexis.com because the certificate for the server has been revoked", or in spanish "Avast ha bloqueado el acceso a https://rpt.cedexis.com porque se ha revocado el certificado del servidor".

[REDACTED]

So it's on tumblr, I have the same problem, I hadn't noticed