On Tuesday, Telegram has blocked a bot that sold Facebook users' phone numbers through the messaging app for hefty sums.

Cybercriminals just lost their revenue-generating bot after Telegram finally blocked it Tuesday. The bot allowed individuals to gain access to millions of Facebook users' phone numbers using the Telegram messaging app.

Motherboard reported that the phone numbers were pulled from a massive database before Facebook was able to fix the security hole back in August 2019. New York Post received info from a support representative of Telegram who said that the bot has already been blocked by Tuesday morning. It did not specifically say exactly when the bot was disabled nor did it give information on the duration that it remained active on the messaging platform.

Those who may have been trying to get the phone number of a Facebook user would just have to enter the Facebook ID that they want, and the bot would be the one to retrieve the phone details. If the phone number is the known value, then the bot would return the Facebook ID.

Since it requires ingenuity to be able to access such a confidential database, the programmers behind the bot profited from it by selling access to the massive information. A test conducted by Motherboard revealed this message from the Telegram bot upon launch: "The bot helps to find out the cellular phone numbers of Facebook users."

New York Post mentioned that the price could start at $20 for one credit, and it could fetch up to a whopping $5,000 for 10,000 credits.

Alon Gal from Hudson Rock, which is a cybersecurity firm, said that the bot claims it can access 533 million Facebook users located in so many countries in the world. He also told Motherboard that it is imperative for the social media giant to inform its users so that "they are less likely to fall victim to different hacking and social engineering attempts."

Hacker sells Facebook phone numbers through a Telegram bot. Photo: Pixabay

Although Facebook told The Post in an email that it has already fixed the issue in August 2019, it does not help those individuals who have linked their phone numbers to their accounts on Facebook before the fix. In September 2019, Facebook already had more than 1.6 billion active users on a daily basis.