The phone rings and the voice on the other end is your son’s. He is nervous, says he got involved in an accident, that he needs money now, and asks you not to tell anyone. The voice has his way of speaking, the same nickname, the same haste.

The scene is an illustrative example, but the script is what the authorities describe. In March 2023, the Federal Trade Commission, the consumer-protection agency of the United States, warned that scammers had started using artificial intelligence to clone the voice of relatives in fake emergency calls. In December 2024, the FBI published a broader alert on the use of generative AI in financial fraud, with cloned audio among the techniques.

The good news is that the defense does not depend on knowing how to identify a fake voice. It depends on a simple habit, agreed beforehand, that works even when the imitation is perfect. This article explains how the scam works, which signs it leaves, and what to do if the money has already gone out.

How the voice is cloned

Voice-cloning programs learn a person’s characteristics from recordings and then generate new sentences with that timbre. The FTC summarizes the point that matters most to an ordinary person: the scammer needs only a short audio clip of the person, which can be taken from content published on the internet, and a cloning program. Source: FTC, consumer alert of March 2023.

Videos on social networks, audio forwarded in groups, and recordings of talks are possible raw material. Someone who publishes little reduces the risk but does not eliminate it, and someone with a public life has no way to hide their own voice.

The FBI lists two uses of audio generated by AI: impersonating people close to you in crisis situations in order to ask for money and imitating voices in order to try to pass voice-authentication systems of financial accounts. The same alert cites texts, images, and videos generated by AI in romance, investment, and fake-document scams. Source: FBI/IC3, alert I-120324-PSA, December 3, 2024.

Why the scam works

The technology is new, but the scam is old. The “fake relative in trouble” already existed by phone and by message. The cloned voice only removes the distrust that the wrong accent or the different way of speaking used to raise.

The rest of the script stays the same, and that is where the scammer’s weakness lies:

  • Urgency. The situation has to be resolved now: bail, a hospital, a debt, a kidnapping. Haste keeps the victim from stopping to check.
  • Emotion. Fear and worry about someone dear reduce attention to the details.
  • Secrecy. The request not to tell anyone serves to prevent the question that would take the story apart.
  • Payment that is hard to reverse. Pix, a transfer, cryptocurrency, or a gift card. The FTC points to the request for a transfer, cryptocurrency, or a gift card as a sign of a scam, because money sent that way is hard to recover.

Notice that none of these four signs depends on the quality of the voice. A perfect imitation still asks for haste, secrecy, and Pix.

The defense that works: hang up and call back

The FTC’s most direct recommendation is not to trust the voice. Hang up and call the person at the number you already know, not at the number that placed the call. If they do not answer, try another relative or a close friend of theirs.

That step resolves most cases for a simple reason: the scammer controls the call he made, but he does not control the person’s real phone. One minute of verification is enough to take apart a story that depends on urgency.

A few precautions make the habit firmer:

  • Do not use the number that called. The number displayed on the screen can be spoofed by software, so it does not prove who is on the other end.
  • Do not accept “I can’t talk right now.” If the person is supposedly without a phone, call whoever would be with them: the coworker, the spouse, the school, the workplace.
  • Hanging up is not rude. A real emergency is still real after two minutes of verification. A scam rarely survives them.

The family code word

The FBI recommends creating with the family a secret word or phrase to confirm identity in situations like this. The idea is old, and it works because the AI copies the voice but does not know what only the family agreed on.

For the code word to fulfill its function:

  • Agree in person, not by a message in a group, which can be read by whoever has access to the phone.
  • Choose something that is not on social networks. A dog’s name, a birthday, and a soccer team are easy to discover on public profiles.
  • Ask for the word; do not offer it. The person who calls needs to say the code. Asking “is it Tico?” gives away the answer.
  • Include the older members and the younger ones. The FTC’s example is precisely that of the grandfather who receives the call from the grandson in trouble, and the younger ones are usually the ones who publish the most audio and video.

If the person on the line changes the subject, gets irritated, or says they forgot the word, treat it as a scam until you manage to speak with the person at the known number.

Reduce the raw material

The FBI suggests, when possible, limiting the online content with your image and your voice, making social-network accounts private, and restricting followers to people you know.

In practice, that means reviewing what stays public: videos talking to the camera, audio in open communities, and live broadcasts. There is no need to disappear from the internet. The measure reduces the amount of material available to whoever is looking for targets with easy audio. For documents handed to sites, Fluxonar describes how to check whether an online tool uploads your file.

Another point in the FBI alert deserves attention: voice should not be the only password. If your bank or carrier offers voice authentication, prefer combining it with another factor, such as a password, an app token, or confirmation on the device itself.

If the money has already gone out by Pix

Even with care, the scam can succeed. In that case, speed matters more than the shame.

1. Contest the transaction in the bank’s app. Since October 1, 2025, the apps of Pix participants are required to offer self-service for the Special Return Mechanism (MED), known as the contest button, for cases of fraud, scam, and coercion. Source: Agência Brasil, October 2025.

When you register the contest, your institution starts the process of recovering the funds. The MED can trace the money transferred to other accounts and request a block on the funds identified. The return is not guaranteed: it depends on the analysis of the fraud and on the amounts available for recovery, and it may be partial. Do not wait for the police report to contest the Pix. Source: Central Bank of Brazil, MED implementation guide.

2. Do not wait. The request can be made within 80 days of the transaction, according to the Central Bank’s MED guide. That is the maximum deadline for contesting, not a reason to delay: registering the scam quickly increases the chance of recovering the funds. Source: Central Bank of Brazil, MED implementation guide.

3. Know what the MED does not cover. A Pix sent by mistake to the wrong key, and a commercial disagreement, such as a product that did not arrive from a real store, are left out. The mechanism is specific to fraud, scam, and coercion.

4. File the report. File the police report, which in many states can be done through the online police station. Keep the number that called, the time, the receipts, and the messages. The bank may ask for that material.

5. Warn the family. Whoever tried it with you may try it with other relatives using the same voice. Warning them soon closes the door on the second victim.

What to take from this text

  • The voice can be fake even when it sounds perfect. Do not use the voice as proof.
  • Haste, secrecy, and irreversible payment are the signs of the scam, not the quality of the audio.
  • Hang up and call back the number you already know.
  • Agree today on a code word with the family, and ask for the word; never offer it.
  • If the Pix has already gone out, use the contest button in the bank’s app immediately and file the report.

The five-minute conversation to agree on the code word is the cheapest measure in this article. It is worth doing at the next family lunch, before someone needs it.

Sources

  • Federal Trade Commission (FTC), Scammers use AI to enhance their family emergency schemes, consumer alert of March 2023: consumer.ftc.gov.
  • FBI, Internet Crime Complaint Center (IC3), Criminals Use Generative Artificial Intelligence to Facilitate Financial Fraud, alert I-120324-PSA, December 3, 2024: ic3.gov.
  • Central Bank of Brazil, Implementation guide for the return procedures (MED): bcb.gov.br.
  • Agência Brasil, The Pix contest button is available to users, October 2025: agenciabrasil.ebc.com.br.