Modern hackers are sophisticated, but much of the technology to ward them off is not. OTP are no longer considered secure as they’re heavily attacked in recent years.
- The two foundations on which OTP over SMS is built — cellular networks and mobile handsets — were completely different when the method is introduced. Security depends on the confidentiality of text messages and the network’s security, neither of which can be guaranteed. Hackers have created specialized Trojans to get around OTP over SMS security. These trojans hijack mobile phones.
- OTP Requires a reliable cell phone signal and battery life.
- May result in occasional SMS delivery failures
- The use of 3rd Party Messaging providers often incurs a per text charge.