CVE-2015-8370

7.4 HIGH

Published: December 16, 2015 Modified: May 06, 2026

Description

Multiple integer underflows in Grub2 1.98 through 2.02 allow physically proximate attackers to bypass authentication, obtain sensitive information, or cause a denial of service (disk corruption) via backspace characters in the (1) grub_username_get function in grub-core/normal/auth.c or the (2) grub_password_get function in lib/crypto.c, which trigger an "Off-by-two" or "Out of bounds overwrite" memory error.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0

Vector String

CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory

http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html

Source: cve@mitre.org

Exploit

http://lists.fedoraproject.org/pipermail/package-announce/2015-December/173703.html

Source: cve@mitre.org

http://lists.fedoraproject.org/pipermail/package-announce/2015-December/174049.html

Source: cve@mitre.org

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00037.html

Source: cve@mitre.org

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00039.html

Source: cve@mitre.org

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00040.html

Source: cve@mitre.org

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00041.html

Source: cve@mitre.org

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00043.html

Source: cve@mitre.org

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00044.html

Source: cve@mitre.org

http://lists.opensuse.org/opensuse-security-announce/2016-01/msg00003.html

Source: cve@mitre.org

http://packetstormsecurity.com/files/134831/Grub2-Authentication-Bypass.html

Source: cve@mitre.org

http://rhn.redhat.com/errata/RHSA-2015-2623.html

Source: cve@mitre.org

http://seclists.org/fulldisclosure/2015/Dec/69

Source: cve@mitre.org

http://www.debian.org/security/2015/dsa-3421

Source: cve@mitre.org

http://www.openwall.com/lists/oss-security/2015/12/15/6

Source: cve@mitre.org

http://www.openwall.com/lists/oss-security/2024/01/15/3

Source: cve@mitre.org

http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html

Source: cve@mitre.org

Patch

http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html

Source: cve@mitre.org

http://www.securityfocus.com/archive/1/537115/100/0/threaded

Source: cve@mitre.org

http://www.securityfocus.com/bid/79358

Source: cve@mitre.org

http://www.securitytracker.com/id/1034422

Source: cve@mitre.org

http://www.ubuntu.com/usn/USN-2836-1

Source: cve@mitre.org

https://security.gentoo.org/glsa/201512-03

Source: cve@mitre.org

http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html

Source: af854a3a-2127-422b-91ae-364da2661108

Exploit

http://lists.fedoraproject.org/pipermail/package-announce/2015-December/173703.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://lists.fedoraproject.org/pipermail/package-announce/2015-December/174049.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00037.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00039.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00040.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00041.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00043.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00044.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://lists.opensuse.org/opensuse-security-announce/2016-01/msg00003.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://packetstormsecurity.com/files/134831/Grub2-Authentication-Bypass.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://rhn.redhat.com/errata/RHSA-2015-2623.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://seclists.org/fulldisclosure/2015/Dec/69

Source: af854a3a-2127-422b-91ae-364da2661108

http://www.debian.org/security/2015/dsa-3421

Source: af854a3a-2127-422b-91ae-364da2661108

http://www.openwall.com/lists/oss-security/2015/12/15/6

Source: af854a3a-2127-422b-91ae-364da2661108

http://www.openwall.com/lists/oss-security/2024/01/15/3

Source: af854a3a-2127-422b-91ae-364da2661108

http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html

Source: af854a3a-2127-422b-91ae-364da2661108

Patch

http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html

Source: af854a3a-2127-422b-91ae-364da2661108

http://www.securityfocus.com/archive/1/537115/100/0/threaded

Source: af854a3a-2127-422b-91ae-364da2661108

http://www.securityfocus.com/bid/79358

Source: af854a3a-2127-422b-91ae-364da2661108

http://www.securitytracker.com/id/1034422

Source: af854a3a-2127-422b-91ae-364da2661108

http://www.ubuntu.com/usn/USN-2836-1

Source: af854a3a-2127-422b-91ae-364da2661108

https://security.gentoo.org/glsa/201512-03

Source: af854a3a-2127-422b-91ae-364da2661108

46 reference(s) from NVD

Quick Stats

CVSS v3 Score

7.4 / 10.0

EPSS (Exploit Probability)

5.1%

90th percentile

Exploitation Status

Not in CISA KEV

Weaknesses (CWE)

CWE-264 CWE-191

Affected Vendors

fedoraproject gnu

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