CVE-2026-74365 Linux CVE debrief

Who should care

Linux kernel maintainers, users, and administrators should assess exposure and verify patch deployment to prevent data corruption. Affected operators, platforms, and security teams must prioritize patch deployment and monitor for potential data corruption issues. Vulnerability management and security teams should review compensating controls for exposed systems while remediation is scheduled and verified.

Why it matters

A vulnerability in the Linux kernel's nvdimm/btt module allows for silent data corruption due to a race condition in BTT lane acquisition. Linux kernel maintainers and users should assess exposure and verify patch deployment to prevent data corruption.

• Data corruption may occur due to concurrent access to BTT lanes
• Verification of patch deployment is necessary to prevent data corruption
• Linux kernel maintainers and users should assess exposure

Technical summary

The Linux kernel's nvdimm/btt module is vulnerable to silent data corruption due to a race condition in BTT lane acquisition. The existing lane model uses a spinlock together with a per-CPU recursion count, which becomes invalid when BTT lanes become preemptible. This issue was resolved by replacing the spinlock-based recursion model with a dynamically allocated per-lane mutex array and taking the lane lock unconditionally. might_sleep() was added to catch any future atomic-context caller. Linux kernel maintainers and users should assess exposure and verify patch deployment to prevent data corruption.

Defensive priority

Linux kernel maintainers and users should assess exposure and verify patch deployment to prevent data corruption.

Recommended defensive actions

• Assess exposure by checking Linux kernel versions and configurations
• Verify patch deployment for nvdimm/btt module
• Monitor for potential data corruption issues
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The issue was found with the ndctl unit test btt-check.sh and resolved by replacing the spinlock-based recursion model with a dynamically allocated per-lane mutex array. This change addresses the race condition in BTT lane acquisition, preventing silent data corruption. Linux kernel maintainers and users should verify patch deployment to ensure data integrity. The patch replaces the spinlock-based recursion model with a dynamically allocated per-lane mutex array and takes the lane lock unconditionally. might_sleep() was added to catch

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.