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net/sched: act_ct: preserve tc_skb_cb across defragmentation

Type: advisorySource: Official CVE List1 source record

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: preserve tc_skb_cb across defragmentation tcf_ct_handle_fragments() calls nf_ct_handle_fragments() without saving and restoring skb->cb. The defrag helper clears IPCB/IP6CB, which aliases the tc_skb_cb/qdisc_skb_cb control buffer. Fragmented traffic through act_ct therefore loses qdisc metadata such as pkt_segs and can trigger WARN_ON_ONCE() in qdisc_pkt_segs() when panic_on_warn is enabled. Save and restore the full tc_skb_cb around nf_ct_handle_fragments(), matching the pattern used by ovs_ct_handle_fragments().

Announced Source revision 1
Original source ↗

CVE-2026-72057

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: cve:CVE-2026-72057

Linux

Source reference: /containers/cna/affected/0/product

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

Linux

Source reference: /containers/cna/affected/1/product

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "0d76daf2013ce1da20eab5e26bd81d983e1c18fb",
        "lessThan": "fb080b6f54835d5d4d11ce3122800e6f0f6689e6",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "ec624fe740b416fb68d536b37fb8eef46f90b5c2",
        "lessThan": "67d6b00a54446c008f52cf70fc0c2ad0c712f85d",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "ec624fe740b416fb68d536b37fb8eef46f90b5c2",
        "lessThan": "2400c4b05d58834b994500a9eec90a37db44187c",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "ec624fe740b416fb68d536b37fb8eef46f90b5c2",
        "lessThan": "5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "ec624fe740b416fb68d536b37fb8eef46f90b5c2",
        "lessThan": "b3d835407846134b0d54637c0281b39bebef831d",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "ec624fe740b416fb68d536b37fb8eef46f90b5c2",
        "lessThan": "f7f45ceb855d9ba1cba594fb3f383255f7013fad",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "ec624fe740b416fb68d536b37fb8eef46f90b5c2",
        "lessThan": "9092e15defbe6c7bc241c306093ca9d358a578e7",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "5.15.13",
        "lessThan": "5.15.217",
        "versionType": "semver"
      }
    ],
    "programFiles": [
      "net/sched/act_ct.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "5.16"
      },
      {
        "status": "unaffected",
        "version": "0",
        "lessThan": "5.16",
        "versionType": "semver"
      },
      {
        "status": "unaffected",
        "version": "5.15.217",
        "versionType": "semver",
        "lessThanOrEqual": "5.15.*"
      },
      {
        "status": "unaffected",
        "version": "6.1.184",
        "versionType": "semver",
        "lessThanOrEqual": "6.1.*"
      },
      {
        "status": "unaffected",
        "version": "6.6.145",
        "versionType": "semver",
        "lessThanOrEqual": "6.6.*"
      },
      {
        "status": "unaffected",
        "version": "6.12.97",
        "versionType": "semver",
        "lessThanOrEqual": "6.12.*"
      },
      {
        "status": "unaffected",
        "version": "6.18.40",
        "versionType": "semver",
        "lessThanOrEqual": "6.18.*"
      },
      {
        "status": "unaffected",
        "version": "7.1.5",
        "versionType": "semver",
        "lessThanOrEqual": "7.1.*"
      },
      {
        "status": "unaffected",
        "version": "7.2",
        "versionType": "original_commit_for_fix",
        "lessThanOrEqual": "*"
      }
    ],
    "programFiles": [
      "net/sched/act_ct.c"
    ],
    "defaultStatus": "affected"
  }
]
Related CVEs
CVE-2026-72057

Source reference: /cveMetadata/cveId

Publisher severity

high

Source reference: /containers/cna/metrics

Event
#41853 · Revision 1
Added to Heist Feed
Publisher date
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