CVE-2026-64568 Linux CVE debrief

Who should care

Linux kernel developers, Linux distribution maintainers, and users of Linux-based systems should be aware of this vulnerability. The vulnerability affects the Linux kernel's mac80211 subsystem and can cause a denial-of-service (DoS) attack or potentially allow an attacker to execute arbitrary code. The vulnerability has a medium severity level, and affected operators, platforms, and security teams should review and apply the patch from the Linux kernel repository. Compensating controls, monitoring, and asset inventory management are also recommended to mitigate the vulnerability. Rollback/change windows and source tracking can also be used to manage the vulnerability. The vulnerability management team should review the CVE record and apply the patch to affected systems. The security team should monitor for potential exploit attempts and review logs for exposed assets that need extra review. The operator should review and update the Linux kernel to the latest version and apply the patch from the Linux kernel repository. The platform team should review compensating controls for exposed systems while remediation is scheduled and verified. The vulnerability management team should track exceptions, retest remediated assets, and close the item only after evidence is documented. The security team should confirm whether affected product deployments exist in managed environments and assign an owner for follow-up. The operator should plan vendor-supported updates or mitigations through normal change control where exposure is confirmed. The platform team should check relevant monitoring, detection, and logs for exposed assets that need extra review. The vulnerability management team should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. The security team should review and update the Linux kernel to the latest version and apply the patch from the Linux kernel repository. The operator should review compensating controls for exposed systems while remediation is scheduled and verified. The platform team should track exceptions, retest remediated assets, and close the item only after evidence is documented. The vuln

Technical summary

The ieee80211_set_unsol_bcast_probe_resp function in the Linux kernel's mac80211 subsystem is vulnerable to a double-free issue. When the function attempts to allocate a new template but fails, it leads to a double-free of the old template. This can cause a denial-of-service (DoS) attack or potentially allow an attacker to execute arbitrary code. The vulnerability is caused by the function calling kfree_rcu on the old template before allocating a new one. If the allocation fails, the function returns -ENOMEM while the link still points to the object already queued for freeing. The affected product is the Linux kernel, and the vulnerability has a medium severity level.

Defensive priority

Medium

Recommended defensive actions

• Apply the patch from the Linux kernel repository
• Review and update Linux kernel to the latest version
• Monitor for potential exploit 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.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The vulnerability was introduced in the Linux kernel's mac80211 subsystem. The issue arises from the ieee80211_set_unsol_bcast_probe_resp function, which calls kfree_rcu on the old template before allocating a new one. If the allocation fails, the function returns -ENOMEM while the link still points to the object already queued for freeing.

Official resources