The security of AuthenTec, a biometrics company purchased by Apple in June, is being called into question when an independent team of security researchers say they found serious vulnerabilities in AuthenTec’s fingerprint scanning software that make it easy for hackers to take control of PCs using the scanners.

According to an article from Business Journal, researchers found that UPEK Protection Suite, which allows users to sign into different applications on their computer using their thumbprint rather than a password, actually stores those passwords in the computer’s registry in a format that is easily decrypted by a hacker.