A Yubico pam-u2f security update has been released for Gentoo Linux.

GLSA 202208-11 : Yubico pam-u2f: Local PIN Bypass vulnerability

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Gentoo Linux Security Advisory GLSA 202208-11
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  https://security.gentoo.org/
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Severity: Low
Title: Yubico pam-u2f: Local PIN Bypass vulnerability
Date: August 10, 2022
Bugs: #792270
ID: 202208-11

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Synopsis
=======
A vulnerability has been discovered in pam-u2f which could allow a local
attacker to bypass PIN entry.

Background
=========
Yubico pam-u2f is a PAM module for FIDO2 and U2F keys.

Affected packages
================
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Package / Vulnerable / Unaffected
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1 sys-auth/pam_u2f < 1.1.1 >= 1.1.1

Description
==========
A logic issue in Yubico pam-u2f could result in the bypass of a PIN
entry requirement when authenticating with FIDO2.

Impact
=====
An attacker with local access to certain applications using pam-u2f for authentication could incorrectly successfully authenticate without entering the authentication PIN.

Workaround
=========
There is no known workaround at this time.

Resolution
=========
All Yubico pam-u2f users should upgrade to the latest version:

# emerge --sync
# emerge --ask --oneshot --verbose ">=sys-auth/pam_u2f-1.1.1"

References
=========
[ 1 ] CVE-2021-31924
  https://nvd.nist.gov/vuln/detail/CVE-2021-31924
[ 2 ] YSA-2021-03

Availability
===========
This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:

  https://security.gentoo.org/glsa/202208-11

Concerns?
========
Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users' machines is of utmost
importance to us. Any security concerns should be addressed to
security@gentoo.org or alternatively, you may file a bug at
  https://bugs.gentoo.org.

License
======
Copyright 2022 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).

The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.

  https://creativecommons.org/licenses/by-sa/2.5