CVE-2015-8370
published 2015-12-16CVE-2015-8370: Multiple integer underflows in Grub2 1.98 through 2.02 allow physically proximate attackers to bypass authentication, obtain sensitive information, or cause a…
PriorityP333high7.4CVSS 3.1
AVLACHPRNUINSUCHIHAH
EPSS
1.10%
62.1th percentile
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.
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | grub2 | < grub2 2.02~beta2-33 (bookworm) | grub2 2.02~beta2-33 (bookworm) |
| fedoraproject | fedora | — | — |
| gnu | grub2 | — | — |
| gnu | grub2 | — | — |
| gnu | grub2 | — | — |
| gnu | grub2 | — | — |
| gnu | grub2 | — | — |
| gnu | grub2 | >= 0 < 2.02~beta2-33 | 2.02~beta2-33 |
| gnu | grub2 | >= 0 < 2.02~beta2-33 | 2.02~beta2-33 |
| gnu | grub2 | >= 0 < 2.02~beta2-33 | 2.02~beta2-33 |
| gnu | grub2 | >= 0 < 2.02~beta2-33 | 2.02~beta2-33 |
| msrc | cbl_mariner_1.0_arm | — | — |
| msrc | cbl_mariner_1.0_x64 | — | — |
CVSS provenance
nvdv3.17.4HIGHCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.06.9MEDIUMAV:L/AC:M/Au:N/C:C/I:C/A:C
osv7.4HIGH
vendor_debian7.4HIGH
vendor_msrc7.4HIGH
vendor_redhat7.4HIGH
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Microsoft
CVE-2015-8370: NIST NVD Details: https://nvd
vendor_msrc·2020-08-11·CVSS 7.4
CVE-2015-8370 [HIGH] CVE-2015-8370: NIST NVD Details: https://nvd
NIST NVD Details: https://nvd.nist.gov/vuln/detail/CVE-2015-8370
Mariner: Mariner
[email protected]: [email protected]
Exploit Status: DOS:N/A
Remediation: grub2
Ubuntu
GRUB vulnerability
vendor_ubuntu·2015-12-15
CVE-2015-8370 GRUB vulnerability
Title: GRUB vulnerability
Summary: GRUB password protection can be bypassed.
Hector Marco and Ismael Ripoll discovered that GRUB incorrectly handled
the backspace key when configured to use authentication. A local attacker
could use this issue to bypass GRUB password protection.
Instructions: After a standard system update you need to reboot your computer to make
all the necessary changes.
Red Hat
grub2: buffer overflow when checking password entered during bootup
vendor_redhat·2015-12-10·CVSS 7.4
CVE-2015-8370 [HIGH] CWE-787 grub2: buffer overflow when checking password entered during bootup
grub2: buffer overflow when checking password entered during bootup
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.
A flaw was found in the way grub2 handled backspace characters entered in username and password prompts. An attacker with access to the system console could use this flaw to bypass grub2 password protection and gain administrative access to the system.
Package: grub (Red Hat Enterprise Linux 5) - Not affected
Pack
Debian
CVE-2015-8370: grub2 - Multiple integer underflows in Grub2 1.98 through 2.02 allow physically proximat...
vendor_debian·2015·CVSS 7.4
CVE-2015-8370 [HIGH] CVE-2015-8370: grub2 - Multiple integer underflows in Grub2 1.98 through 2.02 allow physically proximat...
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.
Scope: local
bookworm: resolved (fixed in 2.02~beta2-33)
bullseye: resolved (fixed in 2.02~beta2-33)
forky: resolved (fixed in 2.02~beta2-33)
sid: resolved (fixed in 2.02~beta2-33)
trixie: resolved (fixed in 2.02~beta2-33)
GHSA
GHSA-jjvg-65v4-v3cq: Multiple integer underflows in Grub2 1
ghsa_unreviewed·2022-05-14
CVE-2015-8370 [MEDIUM] CWE-191 GHSA-jjvg-65v4-v3cq: Multiple integer underflows in Grub2 1
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.
OSV
CVE-2015-8370: Multiple integer underflows in Grub2 1
osv·2015-12-16·CVSS 7.4
CVE-2015-8370 [HIGH] CVE-2015-8370: Multiple integer underflows in Grub2 1
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.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2015-8370 grub2: buffer overflow when checking password entered during bootup [fedora-all]
bugzilla·2015-12-10·CVSS 7.4
CVE-2015-8370 [HIGH] CVE-2015-8370 grub2: buffer overflow when checking password entered during bootup [fedora-all]
CVE-2015-8370 grub2: buffer overflow when checking password entered during bootup [fedora-all]
This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected versions
of Fedora.
For comments that are specific to the vulnerability please use bugs filed
against the "Security Response" product referenced in the "Blocks" field.
For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs
When submitting as an update, use the fedpkg template provided in the next
comment(s). This will include the bug IDs of this tracking bug as well as
the relevant top-level CVE bugs.
Please also mention the CVE IDs being fixed in the RPM changelog and the
fedpkg commit message.
NOTE: this issue affects multiple suppo
Bugzilla
CVE-2015-8370 grub2: buffer overflow when checking password entered during bootup
bugzilla·2015-12-01·CVSS 7.4
CVE-2015-8370 [HIGH] CVE-2015-8370 grub2: buffer overflow when checking password entered during bootup
CVE-2015-8370 grub2: buffer overflow when checking password entered during bootup
A buffer overflow flaw was found in the way grub2 checked the password entered by the user during bootup. A local attacker could use this flaw to circumvent the password check and, potentially, execute arbitrary code on the system.
Discussion:
Created attachment 1100986
Upstream fix
Here's the fix.
---
Created grub2 tracking bugs for this issue:
Affects: fedora-all [bug 1290417]
---
This flaw has been presented at the CCN-CERT conference by the UPV security team:
https://twitter.com/lostinsecurity/status/674925944524640257
---
This issue has been addressed in the following products:
Red Hat Enterprise Linux 7
Via RHSA-2015:2623 https://rhn.redhat.com/errata/RHSA-2015-2623.html
---
Detailed wri
http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.htmlhttp://lists.fedoraproject.org/pipermail/package-announce/2015-December/173703.htmlhttp://lists.fedoraproject.org/pipermail/package-announce/2015-December/174049.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00037.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00039.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00040.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00041.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00043.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00044.htmlhttp://lists.opensuse.org/opensuse-security-announce/2016-01/msg00003.htmlhttp://packetstormsecurity.com/files/134831/Grub2-Authentication-Bypass.htmlhttp://rhn.redhat.com/errata/RHSA-2015-2623.htmlhttp://seclists.org/fulldisclosure/2015/Dec/69http://www.debian.org/security/2015/dsa-3421http://www.openwall.com/lists/oss-security/2015/12/15/6http://www.openwall.com/lists/oss-security/2024/01/15/3http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.htmlhttp://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.htmlhttp://www.securityfocus.com/archive/1/537115/100/0/threadedhttp://www.securityfocus.com/bid/79358http://www.securitytracker.com/id/1034422http://www.ubuntu.com/usn/USN-2836-1https://security.gentoo.org/glsa/201512-03http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.htmlhttp://lists.fedoraproject.org/pipermail/package-announce/2015-December/173703.htmlhttp://lists.fedoraproject.org/pipermail/package-announce/2015-December/174049.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00037.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00039.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00040.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00041.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00043.htmlhttp://lists.opensuse.org/opensuse-security-announce/2015-12/msg00044.htmlhttp://lists.opensuse.org/opensuse-security-announce/2016-01/msg00003.htmlhttp://packetstormsecurity.com/files/134831/Grub2-Authentication-Bypass.htmlhttp://rhn.redhat.com/errata/RHSA-2015-2623.htmlhttp://seclists.org/fulldisclosure/2015/Dec/69http://www.debian.org/security/2015/dsa-3421http://www.openwall.com/lists/oss-security/2015/12/15/6http://www.openwall.com/lists/oss-security/2024/01/15/3http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.htmlhttp://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.htmlhttp://www.securityfocus.com/archive/1/537115/100/0/threadedhttp://www.securityfocus.com/bid/79358http://www.securitytracker.com/id/1034422http://www.ubuntu.com/usn/USN-2836-1https://security.gentoo.org/glsa/201512-03
2015-12-16
Published