Native media reported that the hackers used entry to the accounts to ship spam messages with malicious hyperlinks to customers’ contacts."
Good ol' phishing.
One thing they (mainstream media) failed to mention is they were indeed victims of sim-jacking as well, if ever by simple link phishing. That was througly described by the victims themselves at Congress investigative sessions.
Sadly, in Brazil the current mainstream media is mostly biased towards the previous government and all the people that was arrested by the Car Wash Operation. They won't openly say it ever (in here they're not as transparent as US ones, for example - and the Operation is probably one of the most popular events ever in the country's history), but the ones at mainstream media that won their place last 20 years' government just want their corrupt politicians back in power.
To say the victims there were hacked because they clicked suspicious links by their own will it's not only convenient, but what they actually want the broad population to believe.