It is tempting to think that users are to blame for their own misfortune. If only they'd had a stronger password! If only they didn't re-use credentials! If only they had perfect OpSec! If only...!
Yes, users should probably take better care of their digital credentials and bury them in a digital vault. But there are some things which are simply impossible for a user to protect against. Take, for example, a SIM-swap attack.
You probably have your phone-number tied to all sorts of important services. If you want to recover your email, log in to a bank, or prove your identity - you'll probably need to receive a call or SMS. If an attacker can take over your phone number, they're one step closer to taking over your accounts.
I keep saying "your phone number", but that's a clever lie. The phone number does not belong to you. It belongs to the network operator and they define which SIM the number points to.
This means a suitably authorised person at the telco can point "your" number to a new SIM card. That's helpful if you've lost your SIM but bad if an attacker wants to divert your number.
What can you do to stop this attack? Nothing.
Oh, you can have a strong and unique password on your account, and you can hope your telco uses TOTP and PassKeys. But it turns out that it is possible to bribe telco employees for the low, low price of US$1000.
If your security rests on a phone number, you've effectively outsourced your security to the most bribeable manager employed by your telco.
Now, I said there's nothing you can do. That isn't quite true. You can attempt to pen-test yourself.
Go to your phone company's account. Set a long password and complex password. Change your mother's maiden name to HK2BY@]'PU,:!VQ;}baTj. Turn on every security measure you can find. Call the phone company from a different phone and explain that you lost your phone and want a new SIM card. If they ask for your mother's maiden name, say "Oh, I set it to a long stream of gibberish". If they ask where to send the SIM, give a trusted friend's address. If your phone company is negligent and send out a new SIM on the basis of poor verification, then you should move your number to a more reputable provider.
It's good fun to try and social-engineer a call-centre worker for your own details. But it's probably illegal to try and bribe someone to hijack yourself.
Anyway, please try to remove your phone number as a critical lynchpin in your security regime.
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