CVE-2026-98477 Linux CVE debrief

Who should care

Linux kernel developers and maintainers, Linux distribution vendors, and users of Linux-based systems should review and apply the available patch to prevent exploitation. Additionally, system administrators and security teams responsible for Linux-based systems should be aware of this vulnerability and take steps to mitigate it. This includes reviewing system logs for potential exploitation attempts and implementing additional security measures to protect

Why it matters

A vulnerability in the Linux kernel's perf/core component could lead to system crashes or instability, and potentially allow for privilege escalation or denial-of-service attacks. Linux kernel developers, maintainers, and users should review and apply the available patch to prevent exploitation.

• Potential system crashes or instability due to NULL pointer dereferences
• Increased risk of privilege escalation or denial-of-service attacks
• Need for patching and updating Linux kernel versions to prevent exploitation

Technical summary

The perf_pmu_sched_task() function in the Linux kernel's perf/core component was passing a NULL pmu_ctx to pmu->sched_task(), leading to a kernel NULL pointer dereference. The issue has been resolved by passing &cpc->epc instead, which is the CPU-wide context for the PMU. This change ensures that the correct context is used, preventing the NULL pointer dereference. Affected Linux kernel versions should be patched to prevent exploitation. The vulnerability could allow for system crashes or instability, and potentially enable attackers to gain elevated privileges or disrupt service.

Defensive priority

Medium

Recommended defensive actions

• Review and apply the available patch to the Linux kernel
• Monitor system logs for potential exploitation attempts
• Consider implementing additional security measures to protect against similar vulnerabilities
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record and source references indicate a NULL pointer dereference vulnerability in the Linux kernel's perf/core component. The issue has been resolved by a patch that passes the correct CPU-wide context to pmu->sched_task().

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.