Rahul Sasi, who is the founder and CEO of CloudSEK, a contextual AI business that predicts cyber threats, recently posted the following post on LinkedIn. According to him, it starts with the hacker calling the victim and convincing them to call a specific number, which looks like either **67*<10 digit number> or *405*<10 digit number>. Both numbers trigger call forwarding, which redirects a phone call to another number. Call forwarding is available on most, if not of all, phone carrier’s systems globally and is supported by most modern mobile phones.
**67*<10 digit number> will forward all your calls to the 10 digit number.
*405*<10 digit number> will forward calls, if your number is busy, to the 10 digit number.
The 10-digit number is always a phone number controlled by the hacker.
While the victim is calling one of the numbers, the hacker starts the WhatsApp registration process for the victim’s phone number, and chooses the option to deliver One Time Password (OTP) through phone call. Because of the activated call forwarding, the OTP will travel to the hacker’s phone.
How to mitigate:
- Ignore calls from unknown numbers.
- Don’t make calls to unknown numbers.
- Secure your WhatsApp account with Two-step verification.
Read more about it here.