{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-72243",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-72243"
  ],
  "published": "2026-08-15T06:04:33Z",
  "summary": "selinux: check connect-related permissions on TCP Fast Open",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nselinux: check connect-related permissions on TCP Fast Open\n\nSimilar to Landlock, SELinux was not updated when TCP Fast Open\nsupport was introduced to ensure connect-related permissions are\nchecked when using TCP Fast Open. Update its socket_sendmsg() hook to\ncall selinux_socket_connect() when MSG_FASTOPEN is passed.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N"
    }
  ],
  "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": "6.1.178",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-72243"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/11406d0d7e11b4e525bb2ace2c70107031d058da"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/e507633bf76bccf1a6af27771fb0d6e2862b7eac"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d028bc080a0dcd6a7f8e1ae1bd32dda696505ba3"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/fc633a598206d4f23af782db7c0b5f3a82751d2c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/646ebbc5f2ff9147d084e1213143f091026a611c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/44c74d27d1b9aaa99fa8a83640c1223575262b80"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-18T06:55:05Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 8.4,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - Exploitation requires a confined local process to invoke sendmsg(2)/sendto(2) with MSG_FASTOPEN; the vulnerable selinux_socket_sendmsg() LSM hook runs on the syscall path before TCP fast-open performs its implicit connect.\nAC:L - A confined task with SOCKET__WRITE can reliably trigger the bypass with one sendmsg/sendto using MSG_FASTOPEN and a destination address; TFO client is enabled by default (sysctl_tcp_fastopen=TFO_CLIENT_ENABLE) and no race or special victim state is needed.\nPR:L - The attacker must be an unprivileged process in a SELinux domain that grants socket write but denies connect/name_connect (e.g., confined Android apps, container workloads, hardened service domains); no real root or init-namespace privileges are required.\nUI:N - No victim interaction is required; the confined attacker process directly issues the bypassing syscall without needing another user or administrator to perform any action.\nS:C - Successful exploitation crosses the SELinux MAC confinement boundary, allowing a sandboxed domain to establish outbound TCP/MPTCP connections that connect(2) and name_connect policy would have blocked, escaping the intended network policy scope.\nC:H - Bypassing connect and name_connect mediation lets a confined process open TCP/MPTCP sessions to SELinux-forbidden destinations and read arbitrary response data from those services (internal APIs, metadata endpoints, databases), constituting unauthorized information disclosure.\nI:H - The bypass enables unauthorized outbound connection establishment and transmission of arbitrary application data (including SYN-cookie payload) to hosts and ports explicitly denied by SELinux connect/name_connect rules, violating integrity of the confinement policy.\nA:N - This is a pure SELinux LSM policy-bypass flaw with no kernel memory corruption, panic, oops, hang, or resource exhaustion; exploitation does not impact system availability."
    }
  }
}