GLSA-201512-03 : GRUB: Authentication bypass

Medium Nessus Plugin ID 87516


The remote Gentoo host is missing one or more security-related patches.


The remote host is affected by the vulnerability described in GLSA-201512-03 (GRUB: Authentication bypass)

An integer underflow in GRUB’s username/password authentication code has been discovered.
Impact :

An attacker with access to the system console may bypass the username prompt by entering a sequence of backspace characters, allowing them e.g.
to get full access to GRUB’s console or to load a customized kernel.
Workaround :

There is no known workaround at this time.


All GRUB 2.x users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose '>=sys-boot/grub-2.02_beta2-r8' After upgrading, make sure to run the grub2-install command with options appropriate for your system. See the GRUB2 Quick Start guide in the references below for examples. Your system will be vulnerable until this action is performed.

See Also

Plugin Details

Severity: Medium

ID: 87516

File Name: gentoo_GLSA-201512-03.nasl

Version: $Revision: 2.1 $

Type: local

Published: 2015/12/21

Modified: 2015/12/21

Dependencies: 12634

Risk Information

Risk Factor: Medium


Base Score: 6.9

Vector: CVSS2#AV:L/AC:M/Au:N/C:C/I:C/A:C

Vulnerability Information

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

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

Patch Publication Date: 2015/12/19

Reference Information

CVE: CVE-2015-8370

GLSA: 201512-03