GLSA 202012-06: Linux-PAM: Authentication bypass

http://security.gentoo.org/

Severity:	normal
Title:	Linux-PAM: Authentication bypass
Date:	12/07/2020
Bugs:	#756361
ID:	202012-06

Synopsis

A vulnerability has been found in Linux-PAM, allowing attackers to bypass the authentication process.

Background

Linux-PAM (Pluggable Authentication Modules) is an architecture allowing the separation of the development of privilege granting software from the development of secure and appropriate authentication schemes.

Affected packages

Package	Vulnerable	Unaffected	Architecture(s)
sys-libs/pam	< 1.5.1	>= 1.5.1	All supported architectures

Description

A flaw was found in Linux-Pam in the way it handle empty passwords for non-existing users.

Impact

A remote attacker, who only needs to know a non-existing username, could bypass security restrictions and authenticate as root user.

Workaround

Ensure that root account is protected by a non-empty password.

Resolution

All Linux-PAM users should upgrade to the latest version:

      # emerge --sync
      # emerge --ask --oneshot --verbose ">=sys-libs/pam-1.5.1"

References

CVE-2020-27780

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-202012-06.xml

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.