Twitter on Wednesday revealed that attackers accessed the direct message (DM) inboxes of some of the accounts that were compromised in last week’s security incident.
The attack took place on July 15 and involved the abuse of internal Twitter systems and tools to gain access to high-profile accounts such as those of Jeff Bezos, Mike Bloomberg, Bill Gates, or Elon Musk, and post fake messages promoting a crypto-currency scam.
The messages encouraged account followers to send money to this Bitcoin address, claiming they would be returned double the amount. Over $100,000 were sent to the address within several hours.
Cryptocurrency exchange Coinbase told Forbes that the amount might have been much higher, but that it prevented more than 1,100 of its customers from sending approximately $280,000 worth of Bitcoin to the Twitter hackers’ wallet.
A few days after the incident, Twitter announced that the attackers targeted a total of 130 accounts, but that only some of them were actually compromised.
Over the weekend, the company revealed that the hackers managed to reset the passwords for 45 of the 130 targeted accounts and gain control of them, and that they also downloaded the data associated with 8 of these accounts.
“8 is the number of accounts where an archive of ‘Your Twitter Data’ was downloaded. This includes all of *your* account activity including DMs. None of the YTD downloads impacted Verified accounts,” the company said in a tweet.
On July 22, Twitter also revealed that the attackers accessed the DM inboxes of 36 of the 130 targeted accounts. One of these accounts is that of an elected official in the Netherlands, the social media platform reveals.
“To date, we have no indication that any other former or current elected official had their DMs accessed,” Twitter said in a blog update on Wednesday.
The attack is believed to be the work of hackers interested in the compromise of “original gangster” accounts, or OG accounts, who also engage in SIM swapping activities.
Investigative journalist Brian Krebs managed to link the incident to specific members of the OGUsers forum, some of whom were selling access to Twitter accounts for profit.
According to Krebs, a 21-year-old from the United Kingdom named Joseph O’Connor and a Michigan youngster who has been involved in SIM swapping before, along with several others members of the OGUsers forum, have inside knowledge of how the attack was carried out.
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