CVE-2020-25647

A flaw was found in grub2 in versions prior to 2.06. During USB device initialization, descriptors are read with very little bounds checking and assumes the USB device is providing sane values. If properly exploited, an attacker could trigger memory corruption leading to arbitrary code execution allowing a bypass of the Secure Boot mechanism. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Published: 2021-03-03 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-25647 is rated Moderate Risk (49.2/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.79%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-25647

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.01% 0.79% +0.78%
2 2025-11-21 0.21% 0.01% -0.20%
3 2025-11-18 — 0.21% —

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-25647

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.6 3.1 HIGH
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:P)
Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 0.9 6.0 [email protected]
7.2 2.0 HIGH
AV:L/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 3.9 10.0 [email protected]

Weakness enumeration for CVE-2020-25647

OS Trackers for CVE-2020-25647

vendor priority summary link
alpine high CVE-2020-25647: 1 source package rows (grub); 7 state rows across 7 repos (3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 7, open 0. https://security.alpinelinux.org/vuln/CVE-2020-25647
debian not yet assigned CVE-2020-25647 not yet assigned priority: Debian including 1 source packages (grub2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-25647
gentoo normal CVE-2020-25647: 1 GLSA(s) (202104-05), 1 atom(s) (sys-devel/grub); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2020-25647
redhat medium — https://access.redhat.com/security/cve/CVE-2020-25647
suse high CVE-2020-25647 severity important: SUSE including 443 source package names (amazon/suse-sles-15-sp1-chost-byos-v20210304-hvm-ssd-x86_64, amazon/suse-sles-15-sp1-chost-byos-v20220127-hvm-ssd-x86_64, …), 723 product×package rows across 82 product lines (HPE Helion OpenStack 8, Image SLES12-SP5-Azure-BYOS, … (82 product lines)): Fixed 593, Known Affected 130. https://www.suse.com/security/cve/CVE-2020-25647/
ubuntu medium CVE-2020-25647 medium priority: Ubuntu including 3 source packages (grub2, grub2-signed, grub2-unsigned), 27 status rows across 9 suites (bionic, focal, groovy, hirsute, impish, jammy, trusty, upstream, xenial): not-affected 23, needs-triage 3, DNE 1. https://ubuntu.com/security/CVE-2020-25647

Affected software / configurations for CVE-2020-25647

Vendor Product Version Raw CPE
gnu grub2 < 2.06 cpe:2.3:a:gnu:grub2:*:*:*:*:*:*:*:*
redhat enterprise_linux 7.0 cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.2 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.3 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.3:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.4 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.6 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 7.7 cpe:2.3:o:redhat:enterprise_linux_server_aus:7.7:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 8.2 cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_eus 7.6 cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_eus 7.7 cpe:2.3:o:redhat:enterprise_linux_server_eus:7.7:*:*:*:*:*:*:*
redhat enterprise_linux_server_eus 8.1 cpe:2.3:o:redhat:enterprise_linux_server_eus:8.1:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.4 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.6 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 7.7 cpe:2.3:o:redhat:enterprise_linux_server_tus:7.7:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.2 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_workstation 7.0 cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
netapp ontap_select_deploy_administration_utility — cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*

References for CVE-2020-25647

cvelogic Threat Intelligence