CVE-2020-27749

CVE Details

Release Date:	2021-03-03
Impact:	None	What is this?

Description

A flaw was found in grub2 in versions prior to 2.06. Variable names present are expanded in the supplied command line into their corresponding variable contents, using a 1kB stack buffer for temporary storage, without sufficient bounds checking. If the function is called with a command line that references a variable with a sufficiently large payload, it is possible to overflow the stack buffer, corrupt the stack frame and control execution which could also circumvent Secure Boot protections. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

See more information about CVE-2020-27749 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	6.7
Vector String:	CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Version:	3.0
Attack Vector:	Local
Attack Complexity:	Low
Privileges Required:	High
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	High
Integrity Impact:	High
Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 7 (grub2)	ELSA-2021-0699	2021-03-05
Oracle Linux version 7 (grub2)	ELSA-2021-9076	2021-03-02
Oracle Linux version 8 (grub2)	ELSA-2021-0696	2021-03-05
Oracle Linux version 8 (grub2)	ELSA-2021-9077	2021-03-02