The National Telecommunications Agency (Anatel) advanced in the fight against fraudulent calls, issuing six orders on the 16th with measures aimed at tracking and blocking companies that generated calls with a falsified identifier, known as spoofing.
According to the regulatory agency, only one of the inspected companies was responsible for a total volume of 2.6 million of these types of calls. Spoofing refers to the manipulation of the number displayed on the caller ID, making it diverge from the actual number of the line that initiated the call.
Although there are legitimate uses for this alteration, such as in companies with multiple extensions, the practice is frequently used with malicious and fraudulent intentions. This vulnerability exists due to the legacy protocols and systems (notably SS7) used in voice calls, which did not foresee this type of problem, combined with less competition in the telecommunications sector in the past.
The solution proposed by Verified Origin involves using STIR/SHAKEN protocols to ensure the validation of call identification data. In the issued orders, Anatel ordered that two companies be prohibited from making calls and that detailed reports be produced on calls classified as spoofing, including registration data and routes.
The companies ELO Contact Center Serviços S.A. and Voros Telecomunicações S/A were the targets of the block. Elo sent 1,758,179 calls with a false identifier through the TIM network, while Voros forwarded 2,600,527 fraudulent calls through the Algar, Surf, Datora, and Foco Telecom networks. The block imposed on Elo is valid for one month, but the block on Voros is indefinite, given that the company operated clandestinely in the telephony sector, providing sales services for TIM products and services.
Additionally, the agency required reports on 199 million calls sent by TIM, Surf Telecom, Algar, and Itelco. Specifically regarding the Italian operator, these calls come from abroad to Brazil, originating from the American US Matrix. Anatel's purpose is to discover who the true sender of these calls is to take subsequent measures, such as requesting further blocks.
The actual number of calls could be significantly higher, as the data was collected from samples of one weekly hour and only on routes with 90% or more occurrences of spoofing. Anatel estimates that the real picture could be much more serious than what is shown by the consolidated inspection results. The case of US Matrix is notable because it displays Brazilian mobile numbers when sending international calls to the TIM network. It is important to note that receiving these calls does not imply that the recipients are customers of these companies, as they may only execute interconnectivity, allowing the traffic of these calls to other companies.