{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-31502",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-31502"
  ],
  "published": "2026-04-22T13:57:42Z",
  "summary": "team: fix header_ops type confusion with non-Ethernet ports",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nteam: fix header_ops type confusion with non-Ethernet ports\n\nSimilar to commit 950803f72547 (\"bonding: fix type confusion in\nbond_setup_by_slave()\") team has the same class of header_ops type\nconfusion.\n\nFor non-Ethernet ports, team_setup_by_port() copies port_dev->header_ops\ndirectly. When the team device later calls dev_hard_header() or\ndev_parse_header(), these callbacks can run with the team net_device\ninstead of the real lower device, so netdev_priv(dev) is interpreted as\nthe wrong private type and can crash.\n\nThe syzbot report shows a crash in bond_header_create(), but the root\ncause is in team: the topology is gre -> bond -> team, and team calls\nthe inherited header_ops with its own net_device instead of the lower\ndevice, so bond_header_create() receives a team device and interprets\nnetdev_priv() as bonding private data, causing a type confusion crash.\n\nFix this by introducing team header_ops wrappers for create/parse,\nselecting a team port under RCU, and calling the lower device callbacks\nwith port->dev, so each callback always sees the correct net_device\ncontext.\n\nAlso pass the selected lower device to the lower parse callback, so\nrecursion is bounded in stacked non-Ethernet topologies and parse\ncallbacks always run with the correct device context.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": null,
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-31502"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/420e5aad7ba89e8f79e2dc8327b0c0c24c1c1d53"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/6d3161fa3eee64d46b766fb0db33ec7f300ef52d"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/0a7468ed49a6b65d34abcc6eb60e15f7f6d34da0"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/20491d384d973a63fbdaf7a71e38d69b0659ea55"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/425000dbf17373a4ab8be9428f5dc055ef870a56"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-05T13:16:28Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - An attacker reaches the vulnerable team header_ops path by locally creating/enslaving network devices through rtnetlink and then triggering dev_hard_header()/dev_parse_header() via local packet/socket or network-stack activity on the malformed team device. The required setup is a local kernel networking configuration path rather than an unauthenticated packet-processing path.\nAC:L - The vulnerable topology, such as GRE -> bond -> team, is fully attacker-controlled once the required namespace capabilities are available, and triggering the bad callback is deterministic. There is no race or external timing condition required.\nPR:L - Creating team/bond/GRE devices and enslaving them requires CAP_NET_ADMIN, and packet sockets require CAP_NET_RAW, but both are available to an unprivileged user inside a user and network namespace on systems permitting unprivileged user namespaces. This is therefore low privileges, not real init-namespace root.\nUI:N - No victim interaction is required after the attacker has local access and namespace capabilities. The attacker can configure the devices and trigger the callback directly.\nS:U - The impact is within the same kernel security authority. This is a kernel crash/type-confusion or privilege-impact issue, not a VM escape or cross-scope boundary violation.\nC:H - The bug is a header_ops type confusion where callbacks interpret team private data as another subsystem's private structure, causing attacker-influenced kernel pointer dereferences and potential kernel memory exposure. Following the higher-severity rule for type confusion, confidentiality impact is high.\nI:H - Type confusion in kernel callback dispatch can lead to misinterpreted object pointers and potentially control-flow or write-primitive exploitation beyond the observed crash. Kernel type confusion is scored as high integrity impact.\nA:H - The reported and expected failure mode is a kernel oops/BUG/crash when the inherited callback uses the wrong net_device private layout. This gives high availability impact."
    }
  }
}
