CVE-2020-27749

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.

How to fix CVE-2020-27749

To remediate CVE-2020-27749, upgrade the affected package to a fixed version below.

• —upgrade to 2.06-r0 or later
• —upgrade to 2.04-16 or later

Is CVE-2020-27749 being exploited?

Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 2.06-r0
• from 0, < 2.04-16

CVSS scores

References (2)

• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2020-27749
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2020-27749