CVE-2026-23336
HighIn 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.
CVSS 3.1 score
7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness type
CWE-416CVE-2026-23336 is a Use After Free vulnerability
What is Use After Free?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE
Affected versions
Linux kernel versions
2.6.31
and later are affected. Fixed in
5.10.253,
5.15.203,
6.1.167,
6.6.130,
6.12.77,
6.18.17,
6.19.7,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-23336 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/57e39fe8da573435fa35975f414f4dc17d9f8449
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PatchKernel patch commithttps://git.kernel.org/stable/c/584279ad9ff1e8e7c5494b9fce286201f7d1f9e2
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PatchKernel patch commithttps://git.kernel.org/stable/c/767d23ade706d5fa51c36168e92a9c5533c351a1
Frequently asked questions
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What is CVE-2026-23336?
CVE-2026-23336 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 2.6.31 onward and has been patched in 5.10.253, 5.15.203, 6.1.167 and others. CVE-2026-23336 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-23336?
CVE-2026-23336 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. -
Is there a patch available for CVE-2026-23336?
Yes — CVE-2026-23336 has been patched. Fixed versions include 5.10.253, 5.15.203, 6.1.167 and others. If you are running Linux kernel 2.6.31 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-23336 actively exploited?
No — CVE-2026-23336 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Use After Free (CWE-416)?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. View CWE-416 on MITRE CWE →