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FKIE_CVE-2026-72430

Vulnerability from fkie_nvd - Published: 2026-08-15 06:22 - Updated: 2026-08-17 06:19
Severity
Summary
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.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0c3d8fc87e10e38fe054ece009d6d1f66bef2cd4
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/13b561c893c741635adce3781490a7a1099106c8
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/16e088016f38cf728a0de709c3335cc5a3850476
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1d51aff78f078af1a80e9496c2f4643f4c0ef0a0
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sched/act_ct.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "13b561c893c741635adce3781490a7a1099106c8",
              "status": "affected",
              "version": "70f06c115bcca26ceeebf938e48bc8143668e38b",
              "versionType": "git"
            },
            {
              "lessThan": "1d51aff78f078af1a80e9496c2f4643f4c0ef0a0",
              "status": "affected",
              "version": "70f06c115bcca26ceeebf938e48bc8143668e38b",
              "versionType": "git"
            },
            {
              "lessThan": "0c3d8fc87e10e38fe054ece009d6d1f66bef2cd4",
              "status": "affected",
              "version": "70f06c115bcca26ceeebf938e48bc8143668e38b",
              "versionType": "git"
            },
            {
              "lessThan": "16e088016f38cf728a0de709c3335cc5a3850476",
              "status": "affected",
              "version": "70f06c115bcca26ceeebf938e48bc8143668e38b",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sched/act_ct.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.7"
            },
            {
              "lessThan": "6.7",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_ct: fix nf_connlabels leak on two error paths\n\ntcf_ct_fill_params() calls nf_connlabels_get() (setting put_labels) when\nTCA_CT_LABELS is present, but two later error sites use a bare return\ninstead of \"goto err\", skipping the err: nf_connlabels_put() cleanup.\nThey also precede the \"p-\u003eput_labels = put_labels\" assignment, so the\ntcf_ct_params_free() fallback does not release the count either. Each\nfailed RTM_NEWACTION on these paths leaks one nf_connlabels reference:\nnet-\u003ect.labels_used is incremented and never released. The action is\nreachable with CAP_NET_ADMIN over the netns, i.e. from an unprivileged\nuser namespace on default-userns kernels.\n\nImpact: an unprivileged user with CAP_NET_ADMIN over a network namespace\n(e.g. via user namespaces) leaks one nf_connlabels reference per failed\nRTM_NEWACTION on the two error paths; net-\u003ect.labels_used is never\nreleased.\n\nThe err: label is safe to reach from both sites: p-\u003etmpl is still NULL\nthere (kzalloc\u0027d, not yet assigned) and nf_ct_put(NULL) is a no-op, so\nno inline release is needed."
    }
  ],
  "id": "CVE-2026-72430",
  "lastModified": "2026-08-17T06:19:10.357",
  "metrics": {},
  "published": "2026-08-15T06:22:16.863",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0c3d8fc87e10e38fe054ece009d6d1f66bef2cd4"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/13b561c893c741635adce3781490a7a1099106c8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/16e088016f38cf728a0de709c3335cc5a3850476"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1d51aff78f078af1a80e9496c2f4643f4c0ef0a0"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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