https://www.darkreading.com/risk/cybercriminals-swap-phishing-for-credential-abuse-vuln-exploits/d/d-id/1337019

https://www.businessinsider.com/phishing-scams-getting-more-sophisticated-what-to-look-out-for-2020-2#hackers-will-start-by-targeting-low-level-employees-then-moving-laterally-to-compromise-executives-accounts-1

https://krebsonsecurity.com/2020/02/hackers-were-inside-citrix-for-five-months/

https://www.clearskysec.com/wp-content/uploads/2020/02/ClearSky-Fox-Kitten-Campaign.pdf