CVE-2021-31924 log

Severity Medium
Remote No
Type Authentication bypass
Yubico pam-u2f before 1.1.1 has a logic issue that, depending on the pam-u2f configuration and the application used, could lead to a local PIN bypass. This issue does not allow user presence (touch) or cryptographic signature verification to be bypassed, so an attacker would still need to physically possess and interact with the YubiKey or another enrolled authenticator.

If pam-u2f is configured to require PIN authentication, and the application using pam-u2f allows the user to submit NULL as the PIN, pam-u2f will attempt to perform a FIDO2 authentication without PIN. If this authentication is successful, the PIN requirement is bypassed.
Group Package Affected Fixed Severity Status Ticket
AVG-2001 pam-u2f 1.1.0-1 1.1.1-1 Medium Fixed
Date Advisory Group Package Severity Type
01 Jun 2021 ASA-202106-16 AVG-2001 pam-u2f Medium authentication bypass