Executive brief
A vulnerability was identified in the Linux kernel's performance monitoring subsystem for Intel processors. This component is responsible for tracking hardware performance metrics used by developers and system administrators to optimize software. An exploit could allow a local user to cause system instability or potentially access sensitive information from the computer's memory.
Technical details
An out-of-bounds read vulnerability exists in the Linux kernel's perf subsystem, specifically within the intel_pmu_hw_config function. When Auto Counter Reload (ACR) is active, the kernel may process a group of events that includes software events. Because software event PMUs are not structured as x86_hybrid_pmu objects, the use of the container_of macro in intel_pmu_set_acr_caused_constr results in an invalid memory reference. A local attacker can trigger this by creating specific performance event groups, potentially leading to information disclosure or a kernel crash. The fix introduces an is_x86_event check to ensure only compatible hardware events are processed by the hybrid helper.
Affected products
- Linux Linux Kernel 6.16.1 to 6.18.22, 6.19 to 6.19.12, 7.0-rc1 to 7.0-rc6
Timeline
- 2026-05-01: disclosed
- 2026-05-01: advisory
- 2026-04-11: patched