CVE-2021-20233

Description

A flaw was found in grub2 in versions prior to 2.06. Setparam_prefix() in the menu rendering code performs a length calculation on the assumption that expressing a quoted single quote will require 3 characters, while it actually requires 4 characters which allows an attacker to corrupt memory by one byte for each quote in the input. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Category

8.2
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.29%
Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org
Affected: n/a grub2
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1926263 issue tracking third party advisory patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH3WXZBHT2R/ vendor advisory
https://security.gentoo.org/glsa/202104-05 third party advisory vendor advisory
https://security.netapp.com/advisory/ntap-20220325-0001/ third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-20233?
CVE-2021-20233 has been scored as a high severity vulnerability.
How to fix CVE-2021-20233?
To fix CVE-2021-20233, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-20233 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-20233 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-20233?
CVE-2021-20233 affects n/a grub2.
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