CVE-2026-64413: Linux kernel · netfilter: ebtables: zero chainstack array
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.0 High · fixed in fc7f105451044501a50cfd530cfa3b472c54acbc : patch Linux kernel soon.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in fc7f105451044501a50cfd530cfa3b472c54acbc, cbfe53599eebffd188938ab6774cc41794f6f9d5, 42bef500d07b5769d916e9122a3e3fa3fd2245ef +5
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: ebtables: zero chainstack array sashiko reports: looking at ebtables table translation, could a sparse cpu_possible_mask lead to an uninitialized pointer free? If cpu_possible_mask is sparse (for example, CPU 0 and CPU 2 are possible, but CPU 1 is not), the allocation loop skips CPU 1. If vmalloc_node() fails at CPU 2, the cleanup loop will blindly decrement and call vfree() on newinfo->chainstack[1]. Not a real-world bug, such allocation isn't expected to fail in the first place.
References
- git.kernel.org/stable/c/2ade612967e2cdfb9290ebcb773f302c82f311fa (opens in a new tab)
- git.kernel.org/stable/c/42bef500d07b5769d916e9122a3e3fa3fd2245ef (opens in a new tab)
- git.kernel.org/stable/c/fc7f105451044501a50cfd530cfa3b472c54acbc (opens in a new tab)
- git.kernel.org/stable/c/9e6c5169db423e51dcc66a73fd15409c0d38e088 (opens in a new tab)
- git.kernel.org/stable/c/29bf41a9b59aff9f6197df58641a00037d567ca8 (opens in a new tab)
- git.kernel.org/stable/c/9f74d28e903fa4fdf82f870d0aeadddc8196e41c (opens in a new tab)
- git.kernel.org/stable/c/5ee856e4208acafaaaf7b84824d39b78c21345d6 (opens in a new tab)
- git.kernel.org/stable/c/cbfe53599eebffd188938ab6774cc41794f6f9d5 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)