CVE-2021-20233
Status: ModifiedHigh (8.2)—
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.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
- Base score: 8.2
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.60%
- Percentile among all scored CVEs: 47
- Score date: 10/6/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (8)
CWEs
- CWE-787
- CWE-787
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1926263
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH3WXZBHT2R/
- https://security.gentoo.org/glsa/202104-05
- https://security.netapp.com/advisory/ntap-20220325-0001/
- https://bugzilla.redhat.com/show_bug.cgi?id=1926263
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH3WXZBHT2R/
- https://security.gentoo.org/glsa/202104-05
- https://security.netapp.com/advisory/ntap-20220325-0001/
Raw JSON (NVD)
Show
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