Innovation | Technology

4 threats to watch out for when a hacker gets your phone number

The more personal information we supply online, the greater at risk we are of identity theft, experts say

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Woman sitting in cafe, looking at her phone with concernMobile phones and their numbers are a hot commodity for hackers, who use techniques such as spoofing, porting and mining to access our personal information.(Getty Images/Mixmike)

Passing out your digits is all it takes to put you at risk of identity theft, warn cyber-security experts. 

From account profiles to online registration forms—be it for retailers, hospital records or social media platforms—we are supplying personal information digitally without hesitation or regard for the implications.

“If someone has your phone number, they are likely to have other identity elements as well, so don’t be surprised,” says Claudiu Popa, a certified security and privacy risk adviser and CEO of Informatica Corporation, a Canadian cybersecurity consulting firm. 

In a world where our offline and digital identities are symbiotic, here are some identity theft scams, and mitigation tactics, to watch out for. 


You’ve likely received several of these spammy, or spoofing, calls. The caller poses as police, the Canada Revenue Agency, or the immigration service, demanding payment and threatening jail time, deportation, and so on. Many are falling victim to a potentially financially devastating scam, warn experts. 

“If [call recipients] don’t have that level of awareness, they are a sitting duck, and that’s who [spoofers] are hoping to catch,” says Popa.

According to the Canadian Anti-Fraud Centre, these scams have defrauded Canadians more than $16.7 million since 2014. It has become so prevalent that the Canadian Radio-television and Telecommunications Commission, recently ramped up its efforts to combat it. The commission will require telecom service providers to implement, by next September, a new framework called STIR/SHAKEN (Secure Telephone Identity Revisited/Signature-based Handling of Asserted Information Using Tokens) technology, which enables the recipient to determine before answering whether the call is suspicious or not. In the meantime, the commission, now requires, as of Dec. 19,  that these providers block calls with numbers more than 15 digits long or that can’t be dialed (such as those with a string of letters or zeros), or provide more advanced call-filtering services.

“Legislation would put the responsibility back on the organizations, and that will hit the cellphone carriers,” says Matt Coveart, identity theft expert at DragonFly I.D., an identity restoration service provider. “They are going to have to do more.”


  • Avoid answering any calls received from unknown numbers. 
  • If you do answer the call, immediately hang up and do not answer any questions. 
  • Never give out any personal information (such as social insurance numbers and banking information) without verifying the request is legitimate. 
  • Report any calls received to the Canadian Anti-Fraud Centre.
  • Keep abreast of offerings by your mobile provider to help stop these calls 


Identities are now being compromised by phone porting, whereby the fraudster, with phone number in possession, links that phone to another SIM card, enabling access to its apps, cloud and email accounts and more. 

From there, the fraudster may call the mobile service provider, impersonating the phone owner and make account changes or report the device lost or stolen. They may change passwords on accounts using the “forgot password” option, gaining access through verification codes now sent to them. 

Meanwhile, victims may be locked out of their accounts, unable to call, text or use data. They may fall prey to extortion threats or have their bank accounts drained and credit cards racked up. 

“It’s very targeted. They find an old cellphone bill and try to leverage that information. The representatives believe the device is stolen or lost,” says Coveart. “They [cyber criminals] say they would like to have the phone ported to another device. Once it’s ported to that device … there are all sorts of impersonation scams from that point.”


  • Protect your personal information. Cautiously fill out online forms, only entering what you absolutely need to. Does this company really need your date of birth, gender or marital status? Is it even legal to request it?
  • Contact your mobile service provider to find out what additional security measures are available if your phone is lost or stolen, or has been compromised. 
  • If your identity is hacked, report it to the Canadian Anti-Fraud Centre and your local police force, and immediately contact your financial institutions and credit bureaus. 


According to security firm Wandera, 83 per cent of phishing attacks in 2019 took place in text messages or in apps. Meanwhile, a recent IBM study reported that users are three times more vulnerable to phishing attacks on a mobile device than a desktop. 

Hackers know this, and target accordingly. Similar to email phishing, these fraudulent requests may be urgent or threatening, demanding payment or personal information, and/or encouraging users to click on ransomware-infected links or attachments. They may also be simple requests, including account updates or password confirmations. 

“What people don’t understand about ransomware is that your data gets stolen first,” says Popa. “So that [info] goes out there and it just joins the masses of personal information that is available about anyone going forward and forever.”


  • Never respond to (or click on) suspicious messages, links or attachments sent via text or apps. 
  • Report suspicious messages to your mobile service provider, and anti-fraud centre. 
  • If the message sent looks legitimate, contact the alleged sender (i.e. your bank) before responding or entering any information to confirm receipt.
  • Update any passwords/log-in credentials associated with targeted accounts. 


With access to one piece of personal information, fraudsters can mine for more data to piece together an identity, Popa says. With the amount we share online—from birthdates, to family members, to marital statuses, to employers—we make it easy for them, he adds. 

A quick search of a phone number, he says, can lead to its mobile service  provider. One phone call to that provider can reveal account details when the right questions are asked. One account detail can direct to a social media account. Furthermore, Popa adds, fraudsters can use data they collect from multiple individuals and combine the information to create virtual people.

“It could be a phone number. It could be a picture. It could be a home address, social media profile. Any one of these identity elements can give rise to an opportunity to gather more data about an individual,” he says.

“You can mix someone’s social insurance number with someone’s home address and suddenly you don’t have someone who really exists. That’s called a synthetic identity … and you can multiply your opportunities for making money.”

In an internal report completed last August, and obtained by the Canadian Press through an Access to Information request, Privacy Commissioner Daniel Therrien called out federal political parties for not adequately protecting Canadians personal information and misusing voter data without proper consent. The report states that Canadian privacy policies fall short on setting limits on how data is used, how long it is kept, whether it is accurate, and how it is safeguarded through security systems.


  • When possible, create distinct digital identities across platforms and accounts using pseudonyms or nicknames, different email addresses, fake birthdates, and so on, advises Popa. Keep track of this information for customer service. “People need to understand one thing. The person that they are in real life is different than the digital identity that they have online. Divorce these two concepts,” he says. “The way they do that, is to be as pseudonymous as possible online.”
  • Use an offline password manager and database to keep track, creating new and distinct passphrases, rather than passwords (minimum of 12 characters, including spaces and punctuation), advises Popa. “Type in a sentence. It’s much easier to remember and it’s less likely to guess it.”


With identity theft a top concern for Canadians according to CPA Canada’s 2018 Fraud Survey, its award-winning book, Protecting You and Your Money: A Guide to Avoiding Identity Theft and Fraud, offers practical insight into spotting scams, fraud protection and rebuilding your life if fallen victim to identity theft.