CVE-2023-20596

Ring0 code execution via unvalidated SMI handler input

Published Nov 14, 2023 · Updated Aug 2, 2024

Improper input validation in the SMM Supervisor on affected AMD Ryzen processors allows attackers to execute code at Ring0. During SMM Supervisor initialization, the supervisor accepts insufficiently validated input from a compromised SMI handler; AMD does not identify the field or validation rule. Exploitation requires SMEP and UMIP to be disabled and control of an SMI handler, and successful exploitation compromises confidentiality, integrity, and availability.

CVSS severityUnavailable
Unscored
EPSS probability1.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper input validation in the SMM Supervisor on affected AMD Ryzen processors allows attackers to execute code at Ring0. During SMM Supervisor initialization, the supervisor accepts insufficiently validated input from a compromised SMI handler; AMD does not identify the field or validation rule. Exploitation requires SMEP and UMIP to be disabled and control of an SMI handler, and successful exploitation compromises confidentiality, integrity, and availability.

The record

CVE
CVE-2023-20596
Published
Nov 14, 2023
Updated
Aug 2, 2024
Vendor
AMD
Product
AMD Ryzen 7035 Series Processors with Radeon Graphics (Rembrandt-R)
Classifications
T1068
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Nov 14, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=various

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

AMD · AMD Ryzen 7035 Series Processors with Radeon Graphics (Rembrandt-R)version=various
AMD · AMD Ryzen 6000 Series Processors with Radeon Graphics (Rembrandt)version=various
AMD · AMD Ryzen 7040 Series Mobile Processors with Radeon Graphics (Phoenix)version=various
AMD · AMD Ryzen 5000 Series Desktop Processor with Radeon Graphics (Cezanne)version=various
AMD · AMD Ryzen 7000 Series Desktop Processors with Radeon Graphics (Raphael X3D)version=various
AMD · AMD Ryzen 7000 Series Desktop Processors with Radeon Graphics (Raphael)version=various
AMD · Ryzen 5000 Series Mobile Processors with Radeon Graphics (Cezanne)version=various

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo