Executive brief
A vulnerability was found in OpenSBI, a critical firmware component used in RISC-V computer systems to manage hardware interactions. An attacker with the ability to run code on the system could send a specially crafted request to the performance monitoring component, causing the entire system to crash. This results in a denial of service, potentially disrupting operations and requiring a manual reboot to restore functionality.
Technical details
A denial of service vulnerability exists in OpenSBI 1.3 within the Supervisor Binary Interface (SBI) Performance Monitoring Unit (PMU) extension. The flaw is triggered when a crafted request is sent to SBI function #2, also known as the 'Find and configure a matching counter' function. Specifically, the issue involves a zero-mask firmware crash when processing certain PMU counter configurations. An attacker with local supervisor-level privileges can exploit this to crash the underlying OpenSBI firmware, leading to a complete system halt. A proof-of-concept reproducer has been identified involving zero-mask inputs.
Affected products
- RISC-V OpenSBI 1.3
Timeline
- 2026-07-27: advisory: NVD publication date