CVE-2026-23336 wifi: cfg80211: cancel rfkill_block work in wiphy_unregister()
A use-after-free vulnerability in the Linux kernel's cfg80211 subsystem allows local attackers to potentially execute arbitrary code or escalate privileges.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-23336?
CVE-2026-23336 is a high-severity use after free vulnerability in Linux kernel, published on 25 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
wifi: cfg80211: cancel rfkill_block work in wiphy_unregister()
There is a use-after-free error in cfg80211_shutdown_all_interfaces found by syzkaller:
BUG: KASAN: use-after-free in cfg80211_shutdown_all_interfaces+0x213/0x220 Read of size 8 at addr ffff888112a78d98 by task kworker/0:5/5326 CPU: 0 UID: 0 PID: 5326 Comm: kworker/0:5 Not tainted 6.19.0-rc2 #2 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Workqueue: events cfg80211_rfkill_block_work Call Trace: <TASK> dump_stack_lvl+0x116/0x1f0 print_report+0xcd/0x630 kasan_report+0xe0/0x110 cfg80211_shutdown_all_interfaces+0x213/0x220 cfg80211_rfkill_block_work+0x1e/0x30 process_one_work+0x9cf/0x1b70 worker_thread+0x6c8/0xf10 kthread+0x3c5/0x780 ret_from_fork+0x56d/0x700 ret_from_fork_asm+0x1a/0x30 </TASK>
The problem arises due to the rfkill_block work is not cancelled when wiphy is being unregistered. In order to fix the issue cancel the corresponding work in wiphy_unregister().
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Weakness: CWE-416
Which versions are affected by CVE-2026-23336?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-23336?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-23336 being exploited?
There is no known exploitation of CVE-2026-23336 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-80693, BELL-CVE-2026-23336, DEBIAN-CVE-2026-23336, GHSA-rgr3-h3cv-574x, ROOT-OS-DEBIAN-11-CVE-2026-23336, ROOT-OS-DEBIAN-12-CVE-2026-23336 and 4 more.