ktora forma jest poprawna

Stories of 'cyber-attacks are reported (report) in the media on a regular basis, but it seems very difficult to discover who is responsible for the attacks.
czy
Stories of 'cyber-attacks are being reported (report) in the media on a regular basis, but it seems very difficult to discover who is responsible for the attacks.

oba

are being reported kładzie nacisk na to, że to się dzieje obecnie

W drugim 'on regular basis' ja bym przykładowo zamienił na 'as we speak'.

"on a regular basis' narzuca 'present simple' czyli powinno być - are reported
wstawiłabym 'it is difficult', zamiast it seems

wyguglaj sobie "are being reported on a regular basis"