CVE-2026-64568 Details
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, matching ieee80211_set_probe_resp() and ieee80211_set_s1g_short_beacon().
A double free vulnerability has been identified in the Linux kernel's mac80211 component, specifically within the handling of unsolicited broadcast probe responses. This issue arises when the function ieee80211_set_unsol_bcast_probe_resp calls kfree_rcu on the old response template before successfully allocating a new one. If the allocation fails, the function returns an error while the old template remains queued for freeing. Subsequent updates or access point (AP) teardowns can re-queue the same reference for cleanup, leading to a second free operation. This flaw is detected by the Kernel Address Sanitizer (KASAN) as a double-free error when the RCU sheaf is processed during a software interrupt, causing a memory management error.
Users can apply the latest patches available in the Linux kernel stable tree to address this vulnerability.
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CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
No SSVC data is available for this CVE.
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Weakness Enumeration
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Affected Products
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Change History
3 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Aug 17, 2026 | CVE Modified | kernel.org |
| Aug 8, 2026 | CVE Modified | kernel.org |
| Aug 5, 2026 | New CVE Received | kernel.org |