A seemingly benign group of hackers is taking over the social media accounts of big personalities in the wake of the leak of hundreds of millions of LinkedIn passwords.
The group, which calls itself OurMine Team, claims to have recently hacked the accounts of, Twitter co-founder Biz Stone, Minecraft creator Markus "Notch" Persson, actor Sawyer Hartman, and pop star David Choi, among others.
The only thing these targets have in common is that they are relatively famous, and all have a LinkedIn account. It's unclear how the hackers are taking over the accounts, but there's some circumstantial evidence that supports the theory that they might be using passwords stolen from LinkedIn back in 2012, which are now being traded in the dark web.
In the case of Biz Stone, for example, a spokesperson for his new company Jelly confirmed the hack, but said the hackers didn't get into his Twitter account, but rather "another service that had posting access to his Twitter account."
Considering the link tweeted by the hackers while they had control of this other "service" is a LinkedIn short URL, it's likely that service is actually LinkedIn—and that Stone had previously connected the two accounts, so that his posts on LinkedIn could be reposted on Twitter without having to enter a password.
A LinkedIn spokesperson confirmed that there have been some account takeovers.
"We are aware of this and our investigations team is taking action," the spokesperson told me.
The value of the LinkedIn data, even if it was seemingly old, was precisely that it could open the door to accounts from other services given that people tend to reuse passwords.
"We are giving their accounts back."
"[You can] get access to other shit," the hacker Peace, who is selling the LinkedIn database on a dark web market, told me earlier this week.
In the cases of Persson, Hartman, and Choi, the hackers seem to have compromised not just one service but several, which likely means they were using the same password from their LinkedIn account. (Perrson, Hartman and Choi did not respond to a request for comment.)
The hackers also bragged about taking over a LinkedIn account that appeared to belong to Twitter and Square CEO Jack Dorsey, but a Square representative said this was not his real account.
A member of OurMine Team denied that they were using data from the LinkedIn hack, and said they're using "exploits," and "0days," which are unknown software flaws. The hacker, however, declined to provide any details on what these exploits are.
Strangely, OurMine team doesn't seem to be doing this for nefarious purposes. When in control of other people's accounts, they just try to get the victim's attention to talk to them directly.
"We are giving their accounts back," the hacker told Motherboard. "We are [sic] just teach them how to secure their accounts and after that we are giving their new accounts passwords, […] we are giving them new passwords to choose to be more secured."
Jelly's spokesperson said that the hack "was benign, and settled quickly." But regardless of benign intentions, the group is still hacking into people's accounts, something that not only ethically questionable, but most certainly illegal.
This story has been updated to add LinkedIn's comments.