Two of my favourite security bloggers are
Bruce Schneier at https://www.schneier.com/
Mr Schneieris a highly experienced cryptographer and security analyst.
He’s passionate about security and exposes both the flaws of Govt systems and the abuse of power by the NSA in weakening internet security.
Brian Krebs http://krebsonsecurity.com/
Is a security researcher. He’s an old fashion investigative journalist, who has turned his skills into investigating online security and breaches.
Feel free to suggest to others.