{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-63891",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2026-63891"
  ],
  "published": "2026-07-19T14:56:29Z",
  "summary": "thunderbolt: property: Cap recursion depth in __tb_property_parse_dir()",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nthunderbolt: property: Cap recursion depth in __tb_property_parse_dir()\n\nA DIRECTORY entry's value field is used as the dir_offset for a\nrecursive call into __tb_property_parse_dir() with no depth counter.\nA crafted peer that chains DIRECTORY entries into a back-reference\nloop drives the parser until the kernel stack is exhausted and the\nguard page fires.  Any untrusted XDomain peer (cable, dock, in-line\ninspector, adjacent host) that reaches the PROPERTIES_REQUEST\ncontrol-plane exchange can trigger this without authentication.\n\nThread a depth counter through tb_property_parse() and\n__tb_property_parse_dir(), and reject blocks that exceed\nTB_PROPERTY_MAX_DEPTH = 8.  That is comfortably larger than any\nobserved legitimate XDomain layout.\n\nOperators who do not need XDomain host-to-host discovery can disable\nthe path entirely with thunderbolt.xdomain=0 on the kernel command\nline.",
  "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": "6.1.176",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-63891"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/2b5f47a710172c962ef42d1b732b04d2ad0dce21"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/95839a67ea56ca35732aad7f711404a3127cfe2d"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/0a84ab9271936c11e84e511bb52fc5682f8b6726"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/b4621e5ef63405c317a84b711faf3bd75b3c6a94"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/f31c6d220f455b5af63590302b30e1b932d14599"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/830c8a9b467e7d3a158483d37fa7dc13892b293a"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ed9455ef4bd9babc90f92e526abe3fb68c1a8709"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/928abe19fbf0127003abcb1ea69cabc1c897d0ab"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-07-19T14:56:29Z"
  }
}