CVE-2026-90353 Linux CVE debrief

Who should care

Defenders responsible for Linux kernel-based systems, especially those using the affected mt76 module, should assess their exposure and prioritize patching. They should review system configurations, monitor system logs, and implement compensating controls for exposed systems. Security teams should track exceptions, retest remediated assets, and verify patch application to prevent use-after-free conditions.

Why it matters

This vulnerability can lead to a use-after-free condition in the Linux kernel's mt76 module, potentially allowing attackers to exploit the vulnerability. Defenders should prioritize verifying and applying patches, reviewing system configurations, and monitoring system logs.

• Verify patch application to prevent use-after-free conditions
• Assess system configurations for potential exposure
• Monitor system logs for suspicious activity

Technical summary

The vulnerability is caused by a use-after-free condition in the mt7915_register_ext_phy function of the Linux kernel's mt76 module. When an error occurs during the registration of the main PHY, the function unwinds through free_phy2, which frees the ext PHY hw while it is still registered with mac80211. The vulnerability affects Linux kernel-based systems using the mt76 module. Defenders should prioritize verifying and applying patches for this vulnerability, especially for systems using the affected Linux kernel versions.

Defensive priority

Defenders should prioritize verifying and applying patches for this vulnerability, especially for systems using the affected Linux kernel versions.

Recommended defensive actions

• Verify and apply patches for this vulnerability
• Review system configurations and kernel versions for potential exposure
• Monitor system logs for suspicious activity
• Perform a thorough review of the affected mt76 module and Linux kernel versions
• Implement compensating controls for exposed systems while remediation is scheduled and verified
• Track exceptions and retest remediated assets
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record and NVD entry provide details about the vulnerability, including its CVSS score and vector. However, the corpus does not establish versions, exploitation, impact, or remediation beyond the provided information.

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.