The passage discusses several security vulnerabilities associated with receiving One-Time Passwords (OTPs) via Short Message Service (SMS) for Two-Factor Authentication (2FA). These risks include:

1. SMS message interception: Hackers can intercept OTP messages through a flaw in the SS7 protocol used to transmit them.

2. SIM card hijacking: Thieves can obtain new SIM cards with victim's numbers from mobile phone stores, thereby diverting OTPs and rendering original phones useless.

3. Trojan-infected smartphones: Malware on victims' devices can steal SMS-based OTPs sent by attackers.

4. Physical theft or tampering: If a device is stolen or its SIM card removed and inserted into another smartphone, hackers gain access to stored OTPs via the victim's account credentials.

5. Notification-enabled lock screens: Even with notifications turned off, if victims have enabled notification alerts for incoming messages on their phones' lock screens, attackers can easily intercept these sensitive details.

The passage concludes by noting that while SMS-based 2FA is still widely used for one-time passwords due to its ease of implementation and low cost compared to more advanced alternatives like Google Authenticator or U2F tokens, it remains a less secure option.

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