CVE-2026-31414

Summary

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 Software

VendorProductVersion RangeStatus
LinuxLinuxea781f197d6a835cbb93a0bf88ee1696296ed8aa < 847cb7fe26c5ce5dce0d1a41fac1ea488b7f1781affected
LinuxLinuxea781f197d6a835cbb93a0bf88ee1696296ed8aa < e7ccaa0a62a8ff2be5d521299ce79390c318d306affected
LinuxLinuxea781f197d6a835cbb93a0bf88ee1696296ed8aa < 4bd1b3d839172724b33d8d02c5a4ff6a1c775417affected
LinuxLinuxea781f197d6a835cbb93a0bf88ee1696296ed8aa < b53294bff19e56ada2f230ceb8b1ffde61cc3817affected
LinuxLinuxea781f197d6a835cbb93a0bf88ee1696296ed8aa < 3dfd3f7712b5a800f2ba632179e9b738076a51f0affected
LinuxLinuxea781f197d6a835cbb93a0bf88ee1696296ed8aa < f01794106042ee27e54af6fdf5b319a2fe3df94daffected
LinuxLinux2.6.30affected
LinuxLinux0 < 2.6.30unaffected
LinuxLinux6.1.168 <= 6.1.*unaffected
LinuxLinux6.6.134 <= 6.6.*unaffected
LinuxLinux6.12.81 <= 6.12.*unaffected
LinuxLinux6.18.22 <= 6.18.*unaffected
LinuxLinux6.19.12 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References