One post referred to Chuckling Squad, the group that said it was responsible for breaking Dorsey's account in late August. All the offending tweets have since been deleted.
It is unclear how the perpetrators got into Moretz's account. Twitter said their systems were not compromised in the attack against Dorsey, increasing the possibility that someone either hijacked his SIM card or forged his number. This does not necessarily mean that Moretz fell victim to the same method, but password cracks for brute force are not as likely at a time when two-factor authentication is relatively common.
We asked Twitter for comment. One thing is certain: this is not a great look for the social network, especially when it is not the first time hackers take over high-profile accounts.