Epyc 7h12 FirmwareOperating system · Amd

CVE-2023-20523

MEDIUM · 5.7 CVSS v3.1 Published 2023-01-11
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
62/100
Remediation priority · Elevated
No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
TOCTOU in the ASP may allow a physical attacker to write beyond the buffer bounds, potentially leading to a loss of integrity or denial of service.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A Time-of-Check-Time-of-Use (TOCTOU) race condition in AMD Secure Processor (ASP) allows a physical attacker to trigger an out-of-bounds write, potentially corrupting memory beyond buffer boundaries and causing integrity loss or denial of service.

MitigationApply AMD-provided firmware updates for the Secure Processor; restrict physical access to affected systems as an interim compensating control.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Epyc 7h12 FirmwareOperating system
Affected:< romepi_1.0.0.c
Epyc 7f72 FirmwareOperating system
Affected:< romepi_1.0.0.c
Epyc 7f52 FirmwareOperating system
Affected:< romepi_1.0.0.c
Epyc 7f32 FirmwareOperating system
Affected:< romepi_1.0.0.c
Epyc 7742 FirmwareOperating system
Affected:< romepi_1.0.0.c
Epyc 7702p FirmwareOperating system
Affected:< romepi_1.0.0.c
Epyc 7702 FirmwareOperating system
Affected:< romepi_1.0.0.c
Epyc 7662 FirmwareOperating system
Affected:< romepi_1.0.0.c

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Physical
Complexity
High
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High

CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the AMD Epyc processor model
    Use system information tools such as dmidecode, lscpu, or the system BIOS to identify the exact AMD Epyc processor model number (for example, Epyc 7h12, 7f72, 7f52, 7f32, 7742, 7702p, 7702, or 7662)
    Affected if The processor model matches one of the affected Epyc variants listed in the CVE
  2. Check the AMD Secure Processor firmware version
    Access the AMD Secure Processor (ASP) firmware version through the system BIOS/UEFI setup, AMD's PSP firmware tools, or platform-specific interfaces that report Platform Security Processor version information
    Affected if The firmware version is earlier than romepi_1.0.0.c (the version is shown as a build string or revision number that can be compared against the fixed version)
  3. Verify physical access exposure
    Determine whether the system is accessible to unauthorized physical attackers, such as in unattended data centers, shared hosting environments, or locations where physical security controls are limited
    Affected if Physical access by untrusted individuals is possible, as the CVE specifies the attacker requires physical proximity to exploit the race condition

A system is affected if it contains one of the listed AMD Epyc processor models with Secure Processor firmware versions earlier than romepi_1.0.0.c and is physically accessible to potential attackers.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply AMD-provided firmware updates for the Secure Processor; restrict physical access to affected systems as an interim compensating control.

Recommended fix High confidence

romepi_1.0.0.c or later Epyc firmware version

  1. 1. Identify the exact Epyc model in your system using BIOS or system inventory tools
  2. 2. Download the latest firmware update from AMD's support website for your specific Epyc model
  3. 3. Verify the firmware version includes 'romepi_1.0.0.c' or a later version in the release notes
  4. 4. Apply the firmware update following AMD's standard firmware update procedure (typically via BIOS update, BMC/IPMI firmware update tool, or AMD's firmware update utility)
  5. 5. Verify the installed firmware version post-update matches the fixed release
Caveat Firmware updates carry inherent risks; ensure backup and test in non-production environment first

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Epyc 7h12 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-20523 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-20523 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data