Buffer overflow in GNU Grub2

CVE-2021-20225

A flaw was found in grub2 in versions prior to 2.06. The option parser allows an attacker to write past the end of a heap-allocated buffer by calling certain commands with a large number of specific short forms of options. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.7 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.010 (61.6th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 62nd percentile — 61.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-20225: held from 0.010 to 0.010.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-20225?
CVE-2021-20225 is a medium-severity vulnerability in GNU Grub2, classified under Out-of-bounds Write. CVSS score: 6.7/10. Published 2021-03-03.
How severe is CVE-2021-20225?
Medium severity. CVSS v3 base score is 6.7 out of 10.
Is CVE-2021-20225 known to be exploited?
25 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.