CVE-2024-36347
Description
A flaw was found in AMD processors. This flaw allows an attacker with system administration privileges to exploit an issue in the signature verification in the AMD CPU ROM microcode patch loader, allowing the load of malicious microcode. This issue could impact the integrity of x86 instruction execution, confidentiality, and data integrity in x86 CPU-privileged context and compromise the SMM execution environment.
Statement
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AMD believes this issue is caused by a weakness in the signature verification algorithm and the vulnerability could allow an administrator privileged attacker, the ability to load arbitrary CPU microcode patches. Malicious CPU microcode results in loss of integrity of x86 instruction execution, loss of confidentiality and integrity of data in x86 CPU privileged context and compromise of SMM execution environment.
Mitigation
Mitigation requires updating the BIOS for updating the CPU firmware. The bug affects hardware in processors of the AMD EPYC™ family: Naples, Rome, Milan, Milan-X, Genoa, Genoa-X, Bergamo/Siena and Raphael.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | High | N/A | N/A |
| Privileges Required | High | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Changed | N/A | N/A |
| Confidentiality | High | N/A | N/A |
| Integrity Impact | High | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
Understanding the Weakness (CWE)
Confidentiality,Integrity
Technical Impact: Read Application Data; Modify Application Data; Read Files or Directories; Modify Files or Directories
An attacker could gain access to or modify sensitive data or system resources. This could allow access to protected files or directories including configuration files and files containing sensitive information.
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