The company announced in its official support account that it had "temporarily deactivated the possibility of tweeting via SMS, or text message, to protect people's accounts."
They claim that they made that decision because they found "vulnerabilities that need to be addressed by mobile phone operators." They also ensure that they are working for improve the system authentication system in two steps which uses the phone number associated with the account.
They also announced that they will reactivate this soon "in markets that rely on SMS for trusted communication" while they work "on a long-term strategy for this tool."
This measure comes a few days after the company's CEO Twitter account, Jack Dorsey, was violated when someone managed to access the phone number that was associated in his account with the SIM hacking technique. What is it about? Hackers often trick mobile operators to duplicate the SIM card and get services linked to the victim's number.
Thus, the hacker was able to send tweets via SMS on behalf of the CEO from a mobile phone outside the manager, but not with his phone number. This was made possible by a "security oversight by the mobile provider," the company said.