PT-2020-6594 · Grub2+10 · Grub2+10

Chris Coulson

+1

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Published

2020-11-20

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Updated

2024-06-15

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CVE-2020-27749

CVSS v2.0

7.2

High

VectorAV:L/AC:L/Au:N/C:C/I:C/A:C
Name of the Vulnerable Software and Affected Versions grub2 versions prior to 2.06
Description A flaw was found in grub2 where variable names in the command line are expanded into their corresponding contents using a 1kB stack buffer without sufficient bounds checking. This can lead to a stack buffer overflow if a variable with a large payload is referenced, potentially corrupting the stack frame and controlling execution, which could also circumvent Secure Boot protections. The highest threat from this issue is to data confidentiality and integrity as well as system availability.
Recommendations For versions prior to 2.06, update to version 2.06 or later to resolve the issue. As a temporary workaround, consider restricting the use of variables in the command line to minimize the risk of exploitation. Avoid using variables with large payloads in the command line until the issue is resolved.

Exploit

Fix

Memory Corruption

Stack Overflow

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Weakness Enumeration

Related Identifiers

ALSA-2021:1734
ALT-PU-2021-1969
ALT-PU-2021-3464
AZL-6463
BDU:2022-00338
CESA-2021_0696
CESA-2021_1734
CESA-2021_2566
CVE-2020-27749
DSA-4867-1
MGASA-2021-0315
OESA-2021-1095
OPENSUSE-SU-2021:0462-1
OPENSUSE-SU-2021_0462-1
OPENSUSE-SU-2024:10824-1
RHSA-2021:0696
RHSA-2021:0697
RHSA-2021:0698
RHSA-2021:0699
RHSA-2021:0700
RHSA-2021:0701
RHSA-2021:0702
RHSA-2021:0703
RHSA-2021:0704
RHSA-2021:1734
RHSA-2021:2566
RHSA-2021:2790
RHSA-2021:3675
RHSA-2021_0696
RHSA-2021_0699
RHSA-2021_1734
RHSA-2021_2566
RLSA-2021:1734
RLSA-2021:2566
SUSE-SU-2021:0679-1
SUSE-SU-2021:0681-1
SUSE-SU-2021:0682-1
SUSE-SU-2021:0683-1
SUSE-SU-2021:0684-1
SUSE-SU-2021:0685-1
SUSE-SU-2021:14659-1
SUSE-SU-2021_14659-1
USN-4992-1

Affected Products

Alt Linux
Almalinux
Astra Linux
Centos
Linuxmint
Red Hat
Red Os
Rocky Linux
Suse
Ubuntu
Grub2