CVE-2026-98427 Linux CVE debrief

Who should care

Linux system administrators and maintainers should assess exposure and apply patches as necessary to prevent potential soft lockup issues. They should also monitor system logs for potential issues and consider implementing rate limiting for codel_dequeue() calls. The vulnerability affects Linux kernel deployments, and defenders should review Linux kernel versions and apply patches as necessary.

Why it matters

Linux system administrators and maintainers should assess exposure and apply patches as necessary to prevent potential soft lockup issues.

• Potential for soft lockup issues
• Unprivileged user can trigger the issue
• Denial of service (DoS) potential

Technical summary

The CoDel control law in the Linux kernel's net/sched: codel did not properly bound the dropping loop per dequeue call. This could lead to a soft lockup when an unprivileged user triggers the issue. The fix ensures the control-law step is at least 1 tick and caps the dropping loop at 256 drops per codel_dequeue() call. Affected Linux system administrators and maintainers should assess exposure and apply patches as necessary to prevent potential soft lockup issues. The vulnerability has been addressed in the Linux kernel, and defenders should review Linux kernel versions and monitor system logs for potential issues.

Defensive priority

Medium

Recommended defensive actions

• Review Linux kernel versions and apply patches as necessary
• Monitor system logs for potential soft lockup issues
• Consider implementing rate limiting for codel_dequeue() calls
• 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 item provide details on the vulnerability and its fix in the Linux kernel. The NVD entry is currently empty. Linux system administrators and maintainers should verify the vulnerability details and assess exposure. Evidence limits suggest that further information may be available from the Linux kernel community and vulnerability researchers. Defensive verification tasks include reviewing Linux kernel versions, monitoring system logs, and considering rate limiting for codel_dequeue() calls.

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.