---
cve: "CVE-2026-64568"
severity: "HIGH"
cvss: 7.8
epss: "0.1%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-08-05 08:08:06"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-20T23:27:48+02:00"
---

# CVE-2026-64568

> 7.8 HIGH

## Beschreibung

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().

## CVSS-Vektor

```
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## Patch verfügbar (OSV)

- Kernel ≥ 6.12.101
- Kernel ≥ 6.18.42
- Kernel ≥ 7.1.6

## Referenzen

- <https://git.kernel.org/stable/c/ca27a81cd77b698e5eb586a011bee6800c7ee4bd>
- <https://git.kernel.org/stable/c/d62b55b7c7dc62887d7fd5648fb38f0bfaef53ae>
- <https://git.kernel.org/stable/c/0ace76e410d7f7d813b605825a3e593a79c3958f>
- <https://git.kernel.org/stable/c/1d067abcd37062426c59ec73dbc4e87a63f33fea>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-64568) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_