INACOM, the Angolan comms regulator, has warned phone users about the risk of wangiri following an enormous attack that occurred on the weekend of June 20th and 21st. Although very few details have been made public, it is understood the attack involved hundreds of thousands of calls placed to subscribers in Angola over a 24-hour period. INACOM’s brief statement (in Portuguese) described wangiri as a “phenomenon that affects the mobile phone industry in several countries”. They also said they were working with operators, especially UNITEL, and steps had already been taken to control the situation.
A related announcement from Unitel (in Portuguese) said the wangiri calls appeared to originate from the following countries: Zimbabwe; Sierra Leone; Guinea; Burundi; Mali, Liberia; Congo; Somalia; Montenegro; Serbia; Tajikistan; Latvia; Lithuania; Macedonia; Seychelles; Cuba and Vanuatu.
UNITEL also stated they have a security system that is designed to prevent wangiri fraud. They indicated their controls include detecting and blocking numbers on a daily basis. However, to deal with this attack UNITEL is also playing a recorded warning when customers attempt to call certain international destinations.
Were it not for coronavirus, revenues from international voice calls would have declined again this year. Repeatedly telling customers not to accept or make calls will only hasten the demise of traditional voice services. As INACOM and UNITEL noted, the problem of wangiri is well-known and widespread. That just begs a question about telcos who have failed to take more effective measures to protect their customers and their business.