• [ GLSA 202012-06 ] Linux-PAM: Authentication bypass

    From Thomas Deutschmann@21:1/5 to All on Mon Dec 7 01:50:03 2020
    This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --PFJdBEKP2aT5OGPwQYMLNDygiAsZevoIX
    Content-Type: text/plain; charset=utf-8; format=flowed
    Content-Language: en-US
    Content-Transfer-Encoding: quoted-printable

    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    Gentoo Linux Security Advisory GLSA 202012-06
    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    https://security.gentoo.org/
    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

    Severity: Normal
    Title: Linux-PAM: Authentication bypass
    Date: December 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
    -------------------------------------------------------------------
    1 sys-libs/pam < 1.5.1 >= 1.5.1

    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
    ==========

    [ 1 ] CVE-2020-27780
    https://nvd.nist.gov/vuln/detail/CVE-2020-27780

    Availability
    ============

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

    https://security.gentoo.org/glsa/202012-06

    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 2020 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


    --PFJdBEKP2aT5OGPwQYMLNDygiAsZevoIX--

    -----BEGIN PGP SIGNATURE-----

    wsB5BAABCAAjFiEEExKRzo+LDXJgXHuURObr3Jv2BVkFAl/Nd58FAwAAAAAACgkQRObr3Jv2BVkc mQf/YWK/3ec3aZ3H9UVF+SBOTPSbiHpJ8CGprIfFUPbNLESAclLHzPJBn4gVpVnDW1cwQQcqUNSO 9PNWetZw1e/LzE1x2h3VoUKYyicU1GFNdoMMK8UIhU6IvFcljTR/YHDc2Hb/3WiFcgy+90BQOD09 wjtrwSNIrDHdhD0dKPPRmEsa1cdYukLHHvcKHjVa+yb1r2iDQZLHu3//rB7vgYkCPhyGFw9eNYU0 dTn77zG4L2WiHLzbw+nRMJYOXTDYrfCteQGBFHswCRyOKf9qr33ivKkONL9yWXFpJhlhFOf5oAVN o5YBmexp7PiRY+MzA3TP257GKGurj2MYd+zbQzHn8Q==
    =uqpU
    -----END PGP SIGNATURE-----

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)