{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-23239",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-23239"
  ],
  "published": "2026-03-10T17:28:42Z",
  "summary": "espintcp: Fix race condition in espintcp_close()",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nespintcp: Fix race condition in espintcp_close()\n\nThis issue was discovered during a code audit.\n\nAfter cancel_work_sync() is called from espintcp_close(),\nespintcp_tx_work() can still be scheduled from paths such as\nthe Delayed ACK handler or ksoftirqd.\nAs a result, the espintcp_tx_work() worker may dereference a\nfreed espintcp ctx or sk.\n\nThe following is a simple race scenario:\n\n           cpu0                             cpu1\n\n  espintcp_close()\n    cancel_work_sync(&ctx->work);\n                                     espintcp_write_space()\n                                       schedule_work(&ctx->work);\n\nTo prevent this race condition, cancel_work_sync() is\nreplaced with disable_work_sync().",
  "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-2026-23239"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/f7ad8b1d0e421c524604d5076b73232093490d5c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/664e9df53226b4505a0894817ecad2c610ab11d8"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/022ff7f347588de6e17879a1da6019647b21321b"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/e1512c1db9e8794d8d130addd2615ec27231d994"
    }
  ],
  "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 - The attacker must be a local user to create a TCP socket and set the espintcp ULP via setsockopt(TCP_ULP). This cannot be triggered remotely without local socket access.\nAC:L - The attacker controls both sides of the race: they trigger close() and control the remote peer (e.g., localhost connection) to send TCP ACKs that fire write_space, reliably creating the race condition.\nPR:L - No capability checks exist in the TCP_ULP setsockopt path or espintcp_init_sk(). Any unprivileged local user can set up an espintcp ULP socket and trigger this bug.\nUI:N - No user interaction is required; the attacker autonomously creates the socket, sets the ULP, and triggers the race.\nS:U - The vulnerability is a kernel-level use-after-free that does not cross a security boundary such as a VM or sandbox.\nC:H - The use-after-free on espintcp_ctx and sock structures allows an attacker to control freed object contents via heap spraying, enabling arbitrary kernel memory reads.\nI:H - The use-after-free enables heap spraying and arbitrary write primitives through the freed espintcp_ctx and sock structures, allowing potential kernel code execution.\nA:H - The use-after-free causes kernel crashes (oops/panic) when the work function dereferences freed memory, providing reliable denial of service."
    }
  }
}