CVE-2026-90121 Linux CVE debrief

Who should care

Linux system administrators, security teams, and developers working with the Linux kernel should assess exposure and apply necessary patches or updates. Linux kernel maintainers and security researchers may also be interested in the technical details of the vulnerability. Additionally, operators and platform administrators may need to review and apply patches or updates to prevent potential issues.

Why it matters

The Linux kernel vulnerability in irqchip/gic-v5 requires attention from Linux system administrators and security teams to assess exposure and apply necessary patches or updates.

• System stability may be affected if the vulnerability is not addressed.
• Linux system administrators should review and apply patches or updates to prevent potential issues.
• Security teams should assess exposure and prioritize remediation efforts.

Technical summary

The Linux kernel vulnerability in irqchip/gic-v5 allows for stale per-CPU IRS data after teardown. This can potentially affect system stability. The vulnerability has been addressed in later kernel versions. The affected product context includes Linux kernel deployments using irqchip/gic-v5. The defensive impact includes the need for Linux system administrators and security teams to assess exposure and apply necessary patches or updates. The source-grounded technical framing emphasizes the importance of updating to later kernel versions to mitigate the vulnerability.

Defensive priority

Medium

Recommended defensive actions

• Review Linux kernel versions and assess exposure based on the provided affected versions.
• Apply patches or updates from Linux to address the vulnerability.
• Monitor system stability and perform necessary maintenance to prevent potential issues.
• 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 in the Linux kernel's irqchip/gic-v5. The NVD entry is currently not provided. The evidence is based on the official CVE Program record and the source item from cve_program_cvelist_v5. The known affected scope includes Linux kernel deployments using irqchip/gic-v5. Defenders should verify the affected versions of the Linux kernel and assess exposure.

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.