dbcve.org
Ryzen 5300g FirmwareOperating system · Amd

CVE-2021-46749

HIGH · 7.5 CVSS v3.1 Published 2023-05-09
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable 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
Insufficient bounds checking in ASP (AMD Secure Processor) may allow for an out of bounds read in SMI (System Management Interface) mailbox checksum calculation triggering a data abort, resulting in a potential 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 · high confidence

Insufficient bounds checking in AMD Secure Processor (ASP) allows an out-of-bounds read during SMI (System Management Interface) mailbox checksum calculation, triggering a data abort and potential denial of service.

MitigationApply the AMD firmware update for the Secure Processor that addresses the bounds checking vulnerability in the SMI mailbox checksum routine.

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
Ryzen 5300g FirmwareOperating system
Affected:= cezannepi-fp6_1.0.0.8
Ryzen 5300ge FirmwareOperating system
Affected:= cezannepi-fp6_1.0.0.8
Ryzen 5500 FirmwareOperating system
Affected:= cezannepi-fp6_1.0.0.8
Ryzen 5600 FirmwareOperating system
Affected:= cezannepi-fp6_1.0.0.8
Ryzen 5600g FirmwareOperating system
Affected:= cezannepi-fp6_1.0.0.8
Ryzen 5600ge FirmwareOperating system
Affected:= cezannepi-fp6_1.0.0.8
Ryzen 5600x FirmwareOperating system
Affected:= cezannepi-fp6_1.0.0.8
Ryzen 5700g FirmwareOperating system
Affected:= cezannepi-fp6_1.0.0.8

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
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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 processor model
    Use system information tools (such as CPU-Z, HWiNFO, or the system's BIOS/UEFI information) to determine the exact AMD Ryzen processor model installed in the system
    Affected if The processor is one of the following models: Ryzen 5300g, 5300ge, 5500, 5600, 5600g, 5600ge, 5600x, or 5700g
  2. Check the AMD Secure Processor firmware version
    Use AMD-provided utilities or system firmware tools to query the AMD Secure Processor (ASP) firmware version. This may be available through AMD's hardware monitoring software, BIOS updates section, or specialized firmware querying tools
    Affected if The ASP firmware version is exactly cezannepi-fp6_1.0.0.8
  3. Verify the platform firmware component
    Confirm the firmware package identifier through the system's firmware/BIOS information or AMD update utilities shows the cezannepi-fp6 platform package
    Affected if The firmware package shows cezannepi-fp6 with version 1.0.0.8
  4. Confirm SMI handler is present
    Check that System Management Interface (SMI) handlers are enabled and accessible on the system. This is typically always active on affected systems as SMI is part of the AMD Secure Processor baseline functionality
    Affected if SMI functionality is present and accessible on the system

A system is affected if it contains any of the listed Ryzen processors (5300g through 5700g) AND has the specific AMD Secure Processor firmware version cezannepi-fp6_1.0.0.8 installed.

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 the AMD firmware update for the Secure Processor that addresses the bounds checking vulnerability in the SMI mailbox checksum routine.

Recommended fix Moderate confidence

Firmware version newer than cezannepi-fp6_1.0.0.8 (specific version available from AMD security advisory)

  1. Identify your specific AMD Ryzen processor model (5300g, 5300ge, 5500, 5600, 5600g, 5600ge, 5600x, or 5700g)
  2. Check your current BIOS/firmware version and confirm it is cezannepi-fp6_1.0.0.8
  3. Visit the AMD support website (www.amd.com) and locate the security advisory for CVE-2021-46749
  4. Download the latest BIOS/firmware update for your specific processor/model from AMD or your motherboard manufacturer
  5. Apply the firmware update following the manufacturer's instructions (typically through BIOS update utility or flashing tool)
  6. Verify the firmware has been updated to a version newer than 1.0.0.8 after the update completes
Caveat Firmware updates carry inherent risks; ensure stable power during update process and follow manufacturer flashing instructions precisely

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

Fix this in Ryzen 5300g Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,690
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,304.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-46749 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2021-46749 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