Your own WhatsApp account in the clutches of a hacker. This is an absolute nightmare. We know a hacker and have had the trick for hijacking someone else’s Whatsapp accounts explained to us.
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PC WORLD caught WhatsApp hackers
© Artem Oleshko, Shutterstock
All sorts of things can be done with someone else’s Whatsapp account, which is often difficult to undo: terminate friendships, spread fake news, scrounge money, spread pornographic images from the web in family groups or simply leave groups with hateful comments. The recipients of the messages have no idea that they do not come from their friends, but from a hacker. But how do hackers even manage to hijack someone else’s Whatsapp accounts?
Suddenly no more access to your own Whatsapp
One trick works without the victim having to do anything – this is shown by the example of Julia B. Her Whatsapp account was hacked on February 2, 2022. In relatively quick succession, she received several short messages with a Whatsapp code on her Android smartphone. This is necessary to register a new device for Whatsapp. She didn’t respond. Neither does the following two calls – from the UK with area code +44 and from the USA (state of Alabama) with area code +1. So far so good. Nothing has happened yet. But then Julia is logged out of Whatsapp and no longer has access to her chats. A new registration according to WhatsApp’s instructions for resetting fails because access is now protected using two-factor authentication (2FA). Panic breaks out!
Thanks to end-to-end encryption, the hacker cannot read past chats, but he can write to all contacts – even if he does not know their names because they are not assigned to contacts. And that’s exactly what he does: he writes to Manuel, Julia’s fiancé: “Do you know the girl? Does she want your account back?” Of course she wants that and the hacker is generous. He turns off the two-factor authentication and Julia can re-register her WhatsApp account and access all chats. Nothing happened.
Mailbox hacked – Whatsapp hijacked
But the exciting question remains: How did the hacker take over Julia’s Whatsapp account. She did not share the six-digit registration code. By the way , that was still the hacker ‘s scam last year . A conclusive explanation cannot be found. So Manuel asks the hacker – we call him Fred – via Whatsapp chat about the procedure. Fred then sends several voice messages that are available to PC-WELT. The trick was to interpose Julia’s mailbox, have Whatsapp call you when you register your mobile phone number and then listen to the answering machine. We will omit the exact details at this point.
![These are the traces on the Android smartphone: calls and messages from unknown numbers from abroad. After that, the WhatsApp account was hijacked. These are the traces on the Android smartphone: calls and messages from unknown numbers from abroad. After that, the WhatsApp account was hijacked.](https://bilder.pcwelt.de/4330725_620x310_r.jpg)
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These are the traces on the Android smartphone: calls and messages from unknown numbers from abroad. After that, the WhatsApp account was hijacked.
WhatsApp recommends this for more security
As with the previous scams, the hacker took advantage of the fact that the hijacked Whatsapp account was insufficiently secured. Two-factor authentication (2FA) has been enabled in the app on Android smartphones and iPhones since early 2017. This “two-step verification” ensures that the registration code alone is no longer sufficient to activate Whatsapp. 2FA is off by default and must be turned on by the user in the Whatsapp settings. To do this, go to “Account” and tap on “2-Step Verification”. Then enter a six-digit code as a PIN and confirm it. In addition, enter an e-mail address to reset the numerical code. In the future, Whatsapp will regularly ask for the PIN and will require it as soon as a Whatsapp account is set up.
That’s what the hacker says
When asked, Fred didn’t want to give us an interview. From his chats and voice messages, we were able to learn at least some details and his motives: He just wanted to try out whether the instructions found on the Internet really (still) worked. He has no financial interests. That’s why he gave Julia the account back without causing any damage. He describes the trick as simple, you don’t need to know more than a few GSM codes. The phone numbers he used (see screenshots) are all fake and untraceable. The hack is said to be possible with any Whatsapp account, as long as a mailbox with standard PINs is activated on the smartphone – he simply used Julia’s number at random. It could have happened to others too.