CVE-2026-72430

net/sched: act_ct: fix nf_connlabels leak on two error paths

N/A
Published: August 15, 2026 at 05:56 AM UTC
Updated: August 17, 2026 at 06:19 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
N/A
Exploit prediction
EPSS 0.2%

Description

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: fix nf_connlabels leak on two error paths tcf_ct_fill_params() calls nf_connlabels_get() (setting put_labels) when TCA_CT_LABELS is present, but two later error sites use a bare return instead of "goto err", skipping the err: nf_connlabels_put() cleanup. They also precede the "p->put_labels = put_labels" assignment, so the tcf_ct_params_free() fallback does not release the count either. Each failed RTM_NEWACTION on these paths leaks one nf_connlabels reference: net->ct.labels_used is incremented and never released. The action is reachable with CAP_NET_ADMIN over the netns, i.e. from an unprivileged user namespace on default-userns kernels. Impact: an unprivileged user with CAP_NET_ADMIN over a network namespace (e.g. via user namespaces) leaks one nf_connlabels reference per failed RTM_NEWACTION on the two error paths; net->ct.labels_used is never released. The err: label is safe to reach from both sites: p->tmpl is still NULL there (kzalloc'd, not yet assigned) and nf_ct_put(NULL) is a no-op, so no inline release is needed.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

6.7 ≤ v < 6.12.976.7 ≤ v < 6.18.406.7 ≤ v < 7.1.56.7 ≤ v < 7.26.770f06c115bcca26ceeebf938e48bc8143668e38b
Vendor states this is fixed in 0c3d8fc87e10e38fe054ece009d6d1f66bef2cd4 (fixed)
Vendor states this is fixed in 13b561c893c741635adce3781490a7a1099106c8 (fixed)
Vendor states this is fixed in 16e088016f38cf728a0de709c3335cc5a3850476 (fixed)
Vendor states this is fixed in 1d51aff78f078af1a80e9496c2f4643f4c0ef0a0 (fixed)
Vendor states this is fixed in 6.12.97 (unaffected)
Vendor states this is fixed in 6.18.40 (unaffected)
Vendor states this is fixed in 6.7 (unaffected)
Vendor states this is fixed in 7.1.5 (unaffected)
Vendor states this is fixed in 7.2 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

Quick Info

StatusRECEIVED

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