GLSA-202012-06 : Linux-PAM: Authentication bypass

critical Nessus Plugin ID 143493
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The remote Gentoo host is missing one or more security-related patches.


The remote host is affected by the vulnerability described in GLSA-202012-06 (Linux-PAM: Authentication bypass)

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.


All Linux-PAM users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose '>=sys-libs/pam-1.5.1'

See Also

Plugin Details

Severity: Critical

ID: 143493

File Name: gentoo_GLSA-202012-06.nasl

Version: 1.3

Type: local

Published: 12/7/2020

Updated: 12/28/2020

Dependencies: ssh_get_info.nasl

Risk Information


Risk Factor: Medium

Score: 5.9


Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: E:U/RL:OF/RC:C


Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:gentoo:linux:pam, cpe:/o:gentoo:linux

Required KB Items: Host/local_checks_enabled, Host/Gentoo/release, Host/Gentoo/qpkg-list

Exploit Ease: No known exploits are available

Patch Publication Date: 12/7/2020

Vulnerability Publication Date: 12/18/2020

Reference Information

CVE: CVE-2020-27780

GLSA: 202012-06