Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack_expect: use expect->helper Use expect->helper in ctnetlink and /proc to dump the helper name. Using nfct_help() without holding a reference to the master conntrack is unsafe. Use exp->master->helper in ctnetlink path if userspace does not provide an explicit helper when creating an expectation to retain the existing behaviour. The ctnetlink expectation path holds the reference on the master conntrack and nf_conntrack_expect lock and the nfnetlink glue path refers to the master ct that is attached to the skb.
Affected products
linux: linux kernel
References9
- git.kernel.org/stable/c/3dfd3f7712b5a800f2ba632179e9b738076a51f0 Patch
- git.kernel.org/stable/c/4bd1b3d839172724b33d8d02c5a4ff6a1c775417 Patch
- git.kernel.org/stable/c/847cb7fe26c5ce5dce0d1a41fac1ea488b7f1781 Patch
- git.kernel.org/stable/c/b53294bff19e56ada2f230ceb8b1ffde61cc3817 Patch
- git.kernel.org/stable/c/e7ccaa0a62a8ff2be5d521299ce79390c318d306 Patch
- git.kernel.org/stable/c/f01794106042ee27e54af6fdf5b319a2fe3df94d Patch
- cert-portal.siemens.com/productcert/html/ssa-019113.html
- cert-portal.siemens.com/productcert/html/ssa-082556.html
- cert-portal.siemens.com/productcert/html/ssa-457936.html
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 48 · as of 12 November 2026
- CWE
- CWE-476
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