CVE-2026-90383 Linux CVE debrief

Who should care

Linux kernel developers, administrators, and users should be aware of this vulnerability and take steps to verify and apply patches. Defenders should review system logs for potential exploitation attempts and monitor system performance for anomalies related to GRU TLB miss handling. System administrators and security teams should prioritize verifying and applying patches for Linux kernel versions affected by this vulnerability. Additionally, they should

Why it matters

CVE-2026-90383 is a Linux kernel vulnerability that has been resolved. Defenders should verify and apply patches, review system logs, and monitor system performance.

• Verify Linux kernel patch levels to prevent potential exploitation
• Monitor system performance for anomalies related to GRU TLB miss handling
• Review system logs for potential exploitation attempts

Technical summary

The GRU TLB miss handler vulnerability in the Linux kernel has been resolved by removing the direct walker and sending interrupt faults to user polling mode. This change enables the existing call-OS fallback to retry faults in process context, mitigating potential exploitation risks. The vulnerability was addressed by modifying the GRU TLB miss handler. Defenders should prioritize verifying and applying patches for Linux kernel versions affected by this vulnerability. The technical details of the vulnerability involve the GRU TLB miss handler walking a process's page tables without holding page-table locks or a reference to the mapped page.

Defensive priority

Defenders should prioritize verifying and applying patches for Linux kernel versions affected by this vulnerability.

Recommended defensive actions

• Verify and apply Linux kernel patches for affected versions
• Review system logs for potential exploitation attempts
• Monitor system performance and behavior for anomalies
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• 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

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, but do not specify affected or patched versions. The Linux kernel patch commits are provided as references. To verify and apply patches, defenders should review the Linux kernel patch commits and official advisories for affected versions. The existing call-OS fallback can retry faults in process context, but defenders should still prioritize verifying and applying patches for Linux kernel versions affected by this vulnerability. The GRU TLB miss handler vulnerability

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.