by Kastro CVE-2026-31414
Linux Linux — netfilter: nf_conntrack_expect: use expect->helper
Description · from the CVE record
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
ProductAffectedFixed inSource
Linuxea781f197d6a835cbb93a0bf88ee1696296ed8aa – < 847cb7fe26c5ce5dce0d1a41fac1ea488b7f1781847cb7fe26c5ce5dce0d1a41fac1ea488b7f1781CNA
Linuxea781f197d6a835cbb93a0bf88ee1696296ed8aa – < e7ccaa0a62a8ff2be5d521299ce79390c318d306e7ccaa0a62a8ff2be5d521299ce79390c318d306CNA
Linuxea781f197d6a835cbb93a0bf88ee1696296ed8aa – < 4bd1b3d839172724b33d8d02c5a4ff6a1c7754174bd1b3d839172724b33d8d02c5a4ff6a1c775417CNA
Linuxea781f197d6a835cbb93a0bf88ee1696296ed8aa – < b53294bff19e56ada2f230ceb8b1ffde61cc3817b53294bff19e56ada2f230ceb8b1ffde61cc3817CNA
Linuxea781f197d6a835cbb93a0bf88ee1696296ed8aa – < 3dfd3f7712b5a800f2ba632179e9b738076a51f03dfd3f7712b5a800f2ba632179e9b738076a51f0CNA
Linuxea781f197d6a835cbb93a0bf88ee1696296ed8aa – < f01794106042ee27e54af6fdf5b319a2fe3df94df01794106042ee27e54af6fdf5b319a2fe3df94dCNA
Linux2.6.30–CNA
SIMATIC S7-1500 CPU 1518-4 PN/DP MFPV3.1.6–siemens-SADP
SIMATIC S7-1500 CPU 1518-4 PN/DP MFPV3.1.5–siemens-SADP
SIMATIC S7-1500 CPU 1518-4 PN/DP MFPV3.1.7–siemens-SADP
SIMATIC S7-1500 CPU 1518-4 PN/DP MFPV3.1.6–siemens-SADP
SIMATIC S7-1500 CPU 1518-4 PN/DP MFPV3.1.5–siemens-SADP
Scores by source
Linux (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total