Microsoft’s Windows Hello security, which offers a passwordless method of logging into Windows-powered machines may not be as secure as users think. Microsoft Windows Hello fingerprint authentication was evaluated for security over its fingerprint sensors embedded in laptops. This led to the discovery of multiple vulnerabilities that would allow a threat actor to bypass Windows Hello Authentication completely. 

As reported by Blackwing Intelligence in a blog post, Microsoft's Offensive Research and Security Engineering (MORSE) had asked them to conduct an assessment of the security of the three top fingerprint sensors embedded in laptops, in response to a recent request. 

There was research conducted on three laptops, the Dell Inspiron 15, the Lenovo ThinkPad T14, and the Microsoft Surface Pro Type Cover with Fingerprint ID, which were used in the study. It was discovered that several vulnerabilities in the Windows Hello fingerprint authentication system could be exploited by researchers working on the project.

In addition, The document also reveals that the fingerprint sensors used in Lenovo ThinkPad T14, Dell Inspiron 15, Surface Pro 8 and X tablets made by Goodix, Synaptics, and ELAN were vulnerable to man-in-the-middle attacks due to their underlying technology. 

A premier sensor enabling fingerprint authentication through Windows Hello is not as secure as manufacturers would like. It has been discovered that there are several security flaws in many fingerprint sensors used in many laptops that are compatible with the Windows Hello authentication feature due to the use of outdated firmware. 

It was discovered by researchers at Blackwing Intelligence, a company that conducts research into the security, offensive capabilities, and vulnerability of hardware and software products. The researchers found weaknesses in fingerprint sensors embedded in the devices from Goodix, Synaptics, and ELAN, all of which are manufactured by these manufacturers. 

Using fingerprint reader exploits requires users to already have fingerprint authentication set up on their targeted laptops so that the exploits can work. Three fingerprint sensors in the system are all part of a type of sensor that is known as "match on chip" (MoC), which includes all biometric management functions in the integrated circuit of the sensor itself.

Concept Of Vulnerability Match On Chip As reported by Cyber Security News, this vulnerability is due to a flaw within the concept of the "match on chip" type sensors. Microsoft removed the option of storing some fingerprint templates on the host machine and replaced it with a "match on chip" sensor.  This means that the fingerprint templates are now stored on the chip, thus potentially reducing the concern that fingerprints might be exfiltrated from the host if the host becomes compromised, which could compromise the privacy of your data. 

Despite this, this method has a downside as it does not prevent malicious sensors from spoofing the communication between the sensor and the host, so in this case, an authorized and authenticated user who is using the sensor can easily be fooled. 

There have been several successful attempts at defeating Windows Hello biometric-based authentication systems in the past, but this isn't the first time. This month, Microsoft released two patches (CVE-2021-34466, CVSS score: 6.1), aimed at patching up a security flaw that was rated medium severity in July 2021, and that could allow an adversary to hijack the login process by spoofing the target's face. 

The validity of Microsoft's statement as to whether they will be able to find a fix for the flaws is still unclear; however, this is not the first time Windows Hello, a biometric-based system, has been the victim of attacks. A proof of concept in 2021 showed that by using an infrared photo of a victim with the facial recognition feature of Windows Hello, it was possible to bypass the authentication method. Following this, Microsoft fixed the issue to prevent the problem from occurring again.