CVE-2026-23272: Linux kernel · netfilter: nf_tables: unconditionally bump set->nelems before insertion
Source GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in e3ccb11fc8249759d23326038c8db987ddaabc77 : patch Linux kernel soon.
Data as of 30 Oct 2026, 16:33 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 7.8 |
|---|
- Patch
- Available – fixed in e3ccb11fc8249759d23326038c8db987ddaabc77, def602e498a4f951da95c95b1b8ce8ae68aa733a, ccb8c8f3c1127cf34d18c737309897c68046bf21 +6
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 20 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: unconditionally bump set->nelems before insertion In case that the set is full, a new element gets published then removed without waiting for the RCU grace period, while RCU reader can be walking over it already. To address this issue, add the element transaction even if set is full, but toggle the set_full flag to report -ENFILE so the abort path safely unwinds the set to its previous state. As for element updates, decrement set->nelems to restore it. A simpler fix is to call synchronize_rcu() in the error path. However, with a large batch adding elements to already maxed-out set, this could cause noticeable slowdown of such batches.
References
- nvd.nist.gov/vuln/detail/CVE-2026-23272 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-784472.html (opens in a new tab)
- git.kernel.org/stable/c/022effa9c54903858e443b1225370e6c758d03f6 (opens in a new tab)
- git.kernel.org/stable/c/25841e8d4241c6c3763e70ae95050f8108707b46 (opens in a new tab)
- git.kernel.org/stable/c/25fcaef7948912652905e96922f36583a84fffed (opens in a new tab)
- git.kernel.org/stable/c/6826131c7674329335ca25df2550163eb8a1fd0c (opens in a new tab)
- git.kernel.org/stable/c/86bc4b1a0f672d47ac19f9022432cb6a2e01cb33 (opens in a new tab)
- git.kernel.org/stable/c/ccb8c8f3c1127cf34d18c737309897c68046bf21 (opens in a new tab)
- git.kernel.org/stable/c/def602e498a4f951da95c95b1b8ce8ae68aa733a (opens in a new tab)
- git.kernel.org/stable/c/e3ccb11fc8249759d23326038c8db987ddaabc77 (opens in a new tab)