CVE-2026-0101 in EPYC 9005 Processors
Summary
by MITRE • 11/12/2026
Improper validation of specified quantities in input within AMD Power Management Firmware (PMFW) could allow a local attacker to pass unsanitized input, potentially resulting in a system crash or denial of service.
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Analysis
by VulDB Data Team • 11/12/2026
The vulnerability identified involves an improper validation mechanism for specific quantity inputs within the Advanced Micro Devices Power Management Firmware, commonly referred to as PMFW. This firmware component is critical for managing power states and performance parameters across AMD processors, acting as an intermediary between the operating system's hardware abstraction layer and the physical silicon. The core technical flaw lies in the failure of the firmware to adequately sanitize or validate numerical values passed from higher-level software components before they are processed by internal logic routines. When a local attacker interacts with this interface, typically through privileged APIs or specific driver calls that communicate directly with the PMFW, they can supply malformed or excessively large numeric inputs. Because these quantities are not rigorously checked against expected bounds or logical constraints, the firmware proceeds to execute operations based on invalid data structures. This lack of boundary checking is a classic example of CWE-20 Improper Input Validation, where the system accepts input that it should reject due to its potential to cause unintended behavior.
The operational impact of this vulnerability centers primarily on system stability and availability rather than direct code execution or privilege escalation in most scenarios. When unsanitized inputs trigger internal logic errors within the PMFW, the firmware may enter an undefined state or encounter a fatal exception that it cannot recover from gracefully. This typically results in a hard system crash, requiring a full reboot of the affected machine to restore functionality. In enterprise environments where uptime is critical, such as data centers running high-performance computing workloads, this denial of service capability can lead to significant operational disruptions and financial loss. The attacker does not necessarily need elevated privileges beyond what is required to invoke the specific power management interfaces, making it a potential vector for local denial-of-service attacks if access controls are insufficiently restrictive. This aligns with ATT&CK technique T1499 Endpoint Denial of Service, where an adversary aims to disrupt or deny service to computing resources by exhausting system capacity or causing crashes through malformed inputs.
Mitigation strategies must address both the immediate technical flaw and broader architectural security postures. For end-users and administrators, applying the latest firmware updates provided by AMD is the primary remediation step, as these patches typically include corrected validation logic for input quantities within the PMFW codebase. System integrators should ensure that their BIOS/UEFI implementations are up to date with vendor-recommended versions. From a defensive architecture perspective, implementing strict access controls on the interfaces used to communicate with power management firmware can limit exposure. This includes restricting which user accounts and processes have permission to invoke low-level hardware control commands. Additionally, deploying runtime application self-protection mechanisms or intrusion detection systems that monitor for anomalous patterns in system calls related to power state transitions may help detect exploitation attempts before they result in a crash. Regular auditing of firmware integrity using tools like UEFI Secure Boot can also ensure that any unauthorized modifications to the PMFW are detected and prevented, thereby maintaining the trust boundary between software and hardware components.