CVE-2021-31924

 

Published at: - 26-05-2021 02:15

Last modified: - 10-08-2022 10:15

Total changes: - 6

Description

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.

Common Vulnerability Scoring System (CVSS)

CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

 

Verification logic

 

Reference

• https://www.yubico.com/support/security-advisories/ysa-2021-03
• https://developers.yubico.com/pam-u2f/
• FEDORA-2021-a52d48b1c2-Mailing List, Third Party Advisory
• FEDORA-2021-724f4733e9-Mailing List, Third Party Advisory
• GLSA-202208-11-

 

Keywords

NVD

 

CVE-2021-31924

 

CVE

 

Common vulnerabilities & exposures

 

CVSS

 

Common vulnerability scoring system

 

Security

 

Vulnerabilities

 

Exposures