HMRC warns cyber criminals are harvesting login details to hijack tax returns and cash in.
Cyber thieves are hijacking online tax returns in order to claim fake refunds.
HMRC has admitted it is aware of cases where hackers steal username and password details from shared computers used by taxpayers to complete their online self-assessment tax returns.
Once a return has been filed, fraudsters can use this information to log in and manipulate the figures in order to trigger a refund. Then it’s just a case of nominating a bank account under their control in order to receive the money.
Prime time
The deadline for online self-assessment returns passed at the end of January, so this will have been a prime time to harvest details and doctor returns.
Over nine million people completed online tax returns by last Sunday’s deadline.
HMRC said that security experts have so far checked 3.4 million suspicious claims and identified 17,000 attempts to claim nearly £100 million in bogus tax repayments.
However, HMRC stressed that its computer systems had not been breached.
Jennie Granger, Director General for Enforcement and Compliance said: "Our success in using cutting-edge technology to sift and sort through millions of pieces of data is stopping fraudulent repayments in their tracks. Our highly skilled tax specialists are experts at reacting quickly to identify suspicious activity, protecting tax revenues that fund essential public services."
Check your credit report to spot suspicious activity
How to stay safe
This year HMRC tightened up security with measures like the ‘2 Factor Authentication’ in order to reduce the risk of fraud, but it says users should be careful with their log-in details and password.
HMRC warned against using shared computers like those in an internet café or even in an office to complete their tax return or indeed perform any other financial transactions.
If you notice anything unusual to do with your online tax return, contact HMRC straight away on 0300 200 3310 (open 8am to 8pm, Monday to Friday, and 8am to 4pm on Saturday).
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