CVE-2026-43482
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk2th percentile - higher than 2% of all known CVEs
Summary
In the Linux kernel, a vulnerability in the sched_ext mechanism where preemption between scx_claim_exit() and helper work kick can cause system wedging. Lack of preemption disabling in this critical code path prevents bypass mode activation and stops task scheduling.
Risk Assessment
The organization is at risk of complete system hang (wedging), potentially leading to service disruptions and data loss.
Recommendation
Apply the Linux kernel patch for CVE-2026-43482 immediately, which disables preemption in the critical sched_ext code section.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: sched_ext: Disable preemption between scx_claim_exit() and kicking helper work scx_claim_exit() atomically sets exit_kind, which prevents scx_error() from triggering further error handling. After claiming exit, the caller must kick the helper kthread work which initiates bypass mode and teardown. If the calling task gets preempted between claiming exit and kicking the helper work, and the BPF scheduler fails to schedule it back (since error handling is now disabled), the helper work is never queued, bypass mode never activates, tasks stop being dispatched, and the system wedges. Disable preemption across scx_claim_exit() and the subsequent work kicking in all callers - scx_disable() and scx_vexit(). Add lockdep_assert_preemption_disabled() to scx_claim_exit() to enforce the requirement.