An issue was discovered in certain Apple products. macOS before 10.13 Supplemental Update is affected. The issue involves the "Security" component. It allows attackers to bypass the keychain access prompt, and consequently extract passwords, via a synthetic click.
Apple Security Advisory 2017-10-05-1 - macOS High Sierra 10.13 Supplemental Update is now available and addresses a password hint issue and keychain extraction vulnerabilities.