CVE-2026-23392 (GCVE-0-2026-23392)
Vulnerability from cvelistv5
Published
2026-03-25 10:33
Modified
2026-08-05 12:21
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In 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.
References
Impacted products
Vendor Product Version
Linux Linux Version: 3b49e2e94e6ebb8b23d0955d9e898254455734f8
Version: 3b49e2e94e6ebb8b23d0955d9e898254455734f8
Version: 3b49e2e94e6ebb8b23d0955d9e898254455734f8
Version: 3b49e2e94e6ebb8b23d0955d9e898254455734f8
Version: 3b49e2e94e6ebb8b23d0955d9e898254455734f8
Version: 3b49e2e94e6ebb8b23d0955d9e898254455734f8
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