HOMEVULNERABILITIESCVE-2020-25647
HIGH

CVE-2020-25647

CWE-787Published: March 3, 2021· Updated: Jun 17, 2026

7.6
CVSS v3.1

Official Description

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.

NVD Source

Technical Analysis

CVE-2020-25647 requires local access, meaning attackers must already have a foothold on the target system.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 7.6.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

From a weakness classification perspective (CWE-787): Out-of-bounds write vulnerabilities can lead to data corruption, crashes, or arbitrary code execution.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorPhysical
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeChanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Affected Vendors & Products

Fedora1 product(s)
fedora
gnu1 product(s)
grub2
netapp1 product(s)
ontap select deploy administration utility
Red Hat5 product(s)
enterprise linuxenterprise linux server ausenterprise linux server eusenterprise linux server tusenterprise linux workstation
Source: NVD CPE · 20 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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Official Patches & Advisories

All References (8)

Quick Facts

CVE IDCVE-2020-25647
CVSS Score7.6 / 10
SeverityHIGH
WeaknessCWE-787
CISA KEVNo
Affected4 vendor(s)
PublishedMar 3, 2021

Related CVEs (CWE-787)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2020-25647 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.