The fault allows unauthorised users to log on BKAV (Back Khoa Internetwork Security Centre) advises users of the laptops to abandon the technology until it is fixed.

Face-recognition software harnesses the laptop’s built-in webcam to grant or deny access with a quick reference to stored digital images. This database is created during a short set-up process designed to provide an adequate profile through a series of still images.

Face-recognition gives users an alternative to signing in to their laptops and multiple users can use the software to access their personal accounts.

BKAV says its research shows that intruders can use a printed photo of the laptop owner to log in.

“We found this fault in laptops made by Asus, Lenovo and Toshiba,” said BKAV’s security expert Nguyen Minh Duc, adding that his centre has reported the fault to representatives of the three manufacturers in Vietnam.

BKAV has 10 million users of its Bkis antivirus software. In September, it found a SaveAs Function fault in Google Chrome software and Microsoft’s Window Encoder.