CVE-2026-64568

Technical Description

In the Linux kernel, the following vulnerability has been resolved:

wifi: mac80211: fix unsol_bcast_probe_resp double free on alloc failure

ieee80211_set_unsol_bcast_probe_resp() calls kfree_rcu() on the old

template before allocating the replacement. If the kzalloc() then fails,

it returns -ENOMEM while link->u.ap.unsol_bcast_probe_resp still points

at the object already queued for freeing. A later update or AP teardown

re-queues that same rcu_head; the second free is caught by KASAN when the

RCU sheaf is processed in softirq:

BUG: KASAN: double-free in rcu_free_sheaf (mm/slub.c:5850)

Free of addr ffff88800d06f300 by task exploit/145

...

__rcu_free_sheaf_prepare (mm/slub.c:2634 mm/slub.c:2940)

rcu_free_sheaf (mm/slub.c:5850)

rcu_core (kernel/rcu/tree.c:2617 kernel/rcu/tree.c:2869)

handle_softirqs (kernel/softirq.c:622)

The buggy address belongs to the cache kmalloc-128 of size 128

Queue the old object for kfree_rcu() only after the new one is published,

matchi

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References