CVE-2026-90398 Linux CVE debrief

Who should care

Linux administrators, security teams, and developers working with the Linux kernel's ath11k component should assess potential exposure and verify firmware versions and configurations. They should review Linux kernel configurations and ath11k deployments for potential exposure, monitor for potential exploitation attempts, and plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.

Why it matters

CVE-2026-90398 is a HIGH severity vulnerability in the Linux kernel's ath11k component. Linux administrators, security teams, and developers working with the Linux kernel's ath11k component should assess potential exposure and verify firmware versions and configurations.

• Verify Linux kernel configurations and ath11k deployments for potential exposure
• Monitor for potential exploitation attempts
• Assess firmware versions and configurations

Technical summary

The Linux kernel's ath11k component has a vulnerability (CVE-2026-90398) due to a stride mismatch in mac_phy_caps_parse(). The vulnerability could allow attackers to write past the end of an allocated buffer. The allocation size and pointer stride must be consistent regardless of what length the firmware provides. The issue has been fixed by using kzalloc_objs(), which derives the element size from the pointer type. Linux administrators, security teams, and developers working with the Linux kernel's ath11k component should assess potential exposure and verify firmware versions and configurations.

Defensive priority

Assess Linux kernel configurations and ath11k deployments for potential exposure.

Recommended defensive actions

• Review Linux kernel configurations and ath11k deployments for potential exposure
• Verify firmware versions and configurations
• Monitor for potential exploitation attempts
• 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 NVD entry provide details on the vulnerability, but do not specify affected versions or exploitation details. The vulnerability has been resolved in the Linux kernel. There is no information on public exploitation or specific attacks. Linux administrators, security teams, and developers working with the Linux kernel's ath11k component should assess potential exposure and verify firmware versions and configurations.

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.