CVE-2026-23392
HighIn the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: release flowtable after rcu grace period on error Call synchronize_rcu() after unregistering the hooks from error path, since a hook that already refers to this flowtable can be already registered, exposing this flowtable to packet path and nfnetlink_hook control plane. This error path is rare, it should only happen by reaching the maximum number hooks or by failing to set up to hardware offload, just call synchronize_rcu(). There is a check for already used device hooks by different flowtable that could result in EEXIST at this late stage. The hook parser can be updated to perform this check earlier to this error path really becomes rarely exercised. Uncovered by KASAN reported as use-after-free from nfnetlink_hook path when dumping hooks.
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-2026-23392 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
4.16
and later are affected. Fixed in
6.1.167,
6.6.130,
6.12.78,
6.18.20,
6.19.10,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-23392 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/7e3955b282eae20d61c75e499c75eade51c20060
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PatchKernel patch commithttps://git.kernel.org/stable/c/adee3436ccd29f1e514c028899e400cbc6d84065
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PatchKernel patch commithttps://git.kernel.org/stable/c/c8092edb9a11f20f95ccceeb9422b7dd0df337bd
Frequently asked questions
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What is CVE-2026-23392?
CVE-2026-23392 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 4.16 onward and has been patched in 6.1.167, 6.6.130, 6.12.78 and others. CVE-2026-23392 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-2026-23392?
CVE-2026-23392 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-2026-23392?
Yes — CVE-2026-23392 has been patched. Fixed versions include 6.1.167, 6.6.130, 6.12.78 and others. If you are running Linux kernel 4.16 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-23392 actively exploited?
No — CVE-2026-23392 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 →