Cyber Resilience

CVE-2023-20555

Memory Safety in Amd Ryzen 3 3300 Firmware ≤ comboam4_pi_v1_1.0.0.a

Memory Safety
Published
08 August 2023
Modified
21 November 2024
Patch / advisory
View advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0032 25th percentile
Risk Priority 56 floored blend · peak EPSS

Summary

CVE-2023-20555 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Amd Ryzen 3 3300 Firmware. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 25th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability Data

Insufficient input validation in CpmDisplayFeatureSmm may allow an attacker to corrupt SMM memory by overwriting an arbitrary bit in an attacker-controlled pointer potentially leading to arbitrary code execution in SMM.

CWE(s)
CWE-787

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-20524Same vendor: Amd
CVE-2023-20520Same vendor: Amd
CVE-2024-21980Same vendor: Amd
CVE-2023-31355Same vendor: Amd
CVE-2023-39281Same product: Amd Ryzen 3 5100
CVE-2020-0986Shared CWE-787
CVE-2023-44807Shared CWE-787
CVE-2023-33635Shared CWE-787
CVE-2021-30761Shared CWE-787
CVE-2025-47725Shared CWE-787

Affected Assets

amd
ryzen 3 3300 firmware
≤ comboam4_pi_v1_1.0.0.a · ≤ comboam4v2_pi_1.2.0.a
amd
ryzen 3 3300x firmware
≤ comboam4_pi_v1_1.0.0.a · ≤ comboam4v2_pi_1.2.0.a
amd
ryzen 5 3600 firmware
≤ comboam4_pi_v1_1.0.0.a · ≤ comboam4v2_pi_1.2.0.a
amd
ryzen 5 3600x firmware
≤ comboam4_pi_v1_1.0.0.a · ≤ comboam4v2_pi_1.2.0.a
amd
ryzen 7 3700 firmware
≤ comboam4_pi_v1_1.0.0.a · ≤ comboam4v2_pi_1.2.0.a
amd
ryzen 7 3700x firmware
≤ comboam4_pi_v1_1.0.0.a · ≤ comboam4v2_pi_1.2.0.a
amd
ryzen 9 3800x firmware
≤ comboam4_pi_v1_1.0.0.a · ≤ comboam4v2_pi_1.2.0.a
amd
ryzen 9 3850x firmware
≤ comboam4_pi_v1_1.0.0.a · ≤ comboam4v2_pi_1.2.0.a
amd
ryzen 9 5950x firmware
≤ comboam4_v2_pi_1.2.0.a
amd
ryzen 9 5900x firmware
≤ comboam4_v2_pi_1.2.0.a
+109 more product configuration(s) — see NVD for full list

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure-development practices (static analysis, bounds checking, code review) are the primary means of preventing out-of-bounds writes.

ID.RA-01 partial match
prevents

Vulnerability scanning and recording can discover out-of-bounds write flaws so they can be remediated.

PR.PS-02 partial match
prevents

Patching or replacing vulnerable software directly eliminates known instances of this coding weakness.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development and acceptance can detect and prevent out-of-bounds write defects.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates practices that prevent out-of-bounds writes.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify bounds-checking and safe memory handling.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture and engineering principles reduce the likelihood of buffer overflows.

A.8.28 Secure coding partial match
prevents

Secure coding directly addresses out-of-bounds writes through language choice and coding standards.

A.8.32 Change management partial match
prevents

Change management can enforce review gates that catch unsafe memory operations before deployment.

References