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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

-------------------------------------------------------------------  
 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
[email protected] 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