CVE-2023-20521

mediumpriority · track · 23EPSS 0.003 · 18 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.26% (18th) EPSS

CVSS 5.7 · medium

Is it mine?

129 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

TOCTOU in the ASP Bootloader may allow an attacker with physical access to tamper with SPI ROM records after memory content verification, potentially leading to loss of confidentiality or a denial of service.

cvss

Technical severity, 0–10. One row per scoring source.

5.7

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.3–5.7

v3.15.7mediumCVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hprimary · NVD / NIST USexploitability 0.5 · impact 5.2

v3.15.7mediumAV:P/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.13.3lowCVSS:3.1/AV:P/AC:H/PR:H/UI:N/S:C/C:L/I:N/A:Lsecondary · ENISA EU

v3.13.3lowCVSS:3.1/AV:P/AC:H/PR:H/UI:N/S:C/C:L/I:N/A:Lsecondary · psirt@amd.comexploitability 0.3 · impact 2.7

v3.15.2mediumCVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-367USprimaryCWE-367US

affected products (129)

Products and version ranges known to be affected.

AMD Prozessorall versionscert_bundDEcpe:/h:amd:amd_processor:-
Dell BIOSall versionscert_bundDEcpe:/h:dell:bios:-
Dell Computerall versionscert_bundDEcpe:/o:dell:dell_computer:-
HP Computerall versionscert_bundDEcpe:/h:hp:computer:-
HPE ProLiantall versionscert_bundDEcpe:/h:hp:proliant:-
IBM Power Hardware Management Console V10all versionscert_bundDEcpe:/a:ibm:hardware_management_console:v10
Lenovo BIOSall versionscert_bundDEcpe:/h:lenovo:bios:-
Lenovo Computerall versionscert_bundDEcpe:/h:lenovo:computer:-
Open Source CentOSall versionscert_bundDEcpe:/o:centos:centos:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
AMD 1st Gen AMD EPYC™ Processorsall versionsenisa_euvdEU
AMD 2nd Gen AMD EPYC™ Processorsall versionsenisa_euvdEU
AMD 3rd Gen AMD EPYC™ Processorsall versionsenisa_euvdEU
AMD AMD EPYC™ Embedded 3000all versionsenisa_euvdEU
AMD AMD EPYC™ Embedded 7002all versionsenisa_euvdEU
AMD AMD EPYC™ Embedded 7003all versionsenisa_euvdEU
AMD AMD Ryzen™ Embedded R1000all versionsenisa_euvdEU
AMD AMD Ryzen™ Embedded R2000all versionsenisa_euvdEU

showing 20 of 129

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-2916AMD Prozessor: Mehrere SchwachstellenDeutsch2023-11-14csaf · cert_bundDE
Ein lokaler Angreifer kann mehrere Schwachstellen in AMD Prozessor ausnutzen, um beliebigen Code auszuführen, einen Denial-of-Service-Zustand zu verursachen, Dateien zu manipulieren, vertrauliche Informationen offenzulegen oder seine Privilegien zu erweitern.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund NVD CVE.org MITRE

published 2023-11-14modified 2026-06-17

related (1,061)

Related entries.

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+1056 more

references (11)

External citations — patches, advisories, analysis.

scry

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