Missed calls from numbers starting with 022, 024, 028 and the sophisticated scam trap.

Authorities warn that missed calls from familiar landline numbers are not harmless, but rather a probing tactic used by cybercriminals.

Recently, many mobile phone users have reported receiving frequent missed calls from familiar landline numbers such as 022, 024, and 028. The unusual thing is that these calls only last for a few seconds before being disconnected, repeating many times throughout the day. This has caused many people to fear missing something important and instinctively call back.

Illustrative image.

According to warnings from the Binh Phuoc Provincial Police and authorities in Hanoi , Ho Chi Minh City, Hung Yen, Ninh Binh, etc., this is not a random number misidentification. These missed calls are identified as the initial step in a "hunting" process by high-tech criminal groups, aimed at reviewing and verifying user data.

The Cybersecurity Department analyzed that the perpetrators used automated calling systems to "identify" active phone numbers. If a user answers the call or calls back out of curiosity, the number is immediately marked as a potential target, and then added to a database for illegal transactions or to be used in subsequent scams.

Even more dangerously, some modern systems are capable of recording and analyzing listeners' voices. This data can be exploited for voice spoofing and deepfake technologies, allowing criminals to impersonate banks, telecommunications companies, or government agencies with increasing persuasiveness.

After the initial reconnaissance phase, the perpetrators often move on to direct phone calls, impersonating police officers, prosecutors, bank employees, or telecommunications company staff to exert psychological pressure. They demand that victims provide OTP codes, account information, or trick them into installing fake applications containing malware. In fact, many cases have been recorded where, after just one interaction, all the money in a bank account has been stolen.

Ms. NTH (35 years old, an office worker in Ho Chi Minh City) said that her phone had been receiving missed calls from the 028 number for two consecutive days. Thinking it might be a customer or business partner calling from a landline, she proactively called back. Shortly after, she received another call, the person on the other end claiming to be a bank employee, informing her that her account was showing unusual activity and needed urgent verification. Trusting them because she had just called back the familiar 028 number, Ms. H. followed the instructions, provided the OTP code, and logged into a link sent via text message. Just a few minutes later, all of her bank account, over 120 million VND, had been withdrawn.

In light of this situation, the police advise people to absolutely not call back or text back any unknown numbers that appear to be making prank calls, especially those with a "+" sign in front. If repeatedly bothered, users should proactively block the number and report the spam call to the network provider's hotline 5656.

Most importantly, people need to remember the "three no's" principle: do not provide personal information, do not transfer money, and do not install strange applications based on instructions received over the phone, regardless of who the caller claims to be. In the context of increasingly sophisticated high-tech crime, individual vigilance is the most effective defense against personal property and data theft.

Mr. Vu Ngoc Son, Head of Technology Department, National Cyber ​​Security Association (NCA): "High-tech criminals are exploiting loopholes in the awareness of the public and businesses. We need to strengthen community education and apply more advanced fraud detection tools." He also recommended enhancing legal capacity and international cooperation to combat criminal organizations using high technology.

How to check for unknown phone numbers that call you to avoid being scammed.

Call customer service hotline.

Mobifone network

To check your phone number, press key 4 on the 900 hotline (free of charge).

MobiPhone Customer Service Hotline: 9090 (call charges are 200 VND/minute for prepaid subscribers, postpaid subscribers get free calls).

VinaPhone network

Call 900, press key 4 (applies to prepaid subscribers).

Hotline numbers 9191 or 18001091 (applicable to all subscribers).

Vietnamobile network

Calling 123 is the number for Vietnamobile's customer service hotline.

Calling 789 is the number for Vietnamobile's customer service hotline.

Viettel network

Viettel customer support hotline: 18008098 and 198 (speak to a support representative).

Product and service information hotline: 197 (automatic answering).

Additionally, when receiving spam calls or calls with fraudulent intent, people can report them to the number 156 through two methods: sending a text message or calling 156.

Source: https://khoahocdoisong.vn/cuoc-goi-nhay-may-dau-so-022-024-028-va-cai-bay-lua-dao-tinh-vi-post2149081710.html