SMS is one of the most direct ways for businesses to reach users, but it can be abused for fraud. SMS abuse prevention requires a multi-layered defense that includes smart CAPTCHAs, scalability, and AI detection.

Smishing: Criminals use SMS abuse prevention to send fake alerts or notifications to trick victims into sharing their credentials or clicking on links that download malware onto the device. Smishing can result in financial loss and damage to customer trust.

How to Block Abusive IP Addresses Automatically

SMiShing can also be used to spread fake logins, account verification requests, and two-factor authentication codes. These messages can cause delays and add operational costs for real customers, drain prepaid accounts, or intercept sensitive data.

Attackers register premium-rate phone numbers through certain MNOs and then leverage bots to incessantly send verification messages for two-factor authentication, password resets, and other services. Each message incurs a charge and attackers collect a portion of the revenue. This is known as SMS pumping, and it can result in inflated SMS costs, service interruptions, or depleted prepaid balances.

Implementing a multi-layered defence against automated attacks includes adding strong verification checks to signup forms. CAPTCHA tools like GeeTest’s can distinguish bots from human users by analyzing mouse movement, typing speed, and other behavioral biometrics to spot signs of automation. In addition, implementing rate limiting on client IPs can prevent repeated messaging from risky devices or regions. Combined with other security methods, these can prevent SMS spam and help limit financial losses from unauthorized messaging.