{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-63889",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-63889"
  ],
  "published": "2026-07-19T14:56:29Z",
  "summary": "scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: scsi_transport_fc: Widen FPIN pname walker counter to u32\n\nAn adjacent Fibre Channel fabric actor that can deliver an FPIN ELS\nframe to an lpfc or qla2xxx Linux initiator can trigger a non-return in\nthe generic FC transport. This is not a local userspace or IP network\npath; the attacker must be able to inject fabric traffic, for example as\na compromised switch or fabric controller, or as a same-zone N_Port on a\nfabric that permits source spoofing.\n\nThe Link-Integrity and Peer-Congestion FPIN walkers used a u8 loop\ncounter against the 32-bit on-wire pname_count field, and did not bound\npname_count by the descriptor body already validated by the TLV walker.\nA pname_count of 256 therefore wraps the counter and keeps the loop\ncondition true indefinitely.\n\nFactor the shared pname_list[] walk into one helper, widen the counter\nto u32, and clamp pname_count against the entries that fit in the\ndescriptor body before iterating.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/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": "6.1.176",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-63889"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/07776b7779c9426982c1ad74aad91bd531593790"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/29f126f09e34a425b376b3646c89aa7cc18b142c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/163bd704d7515c3df6c2e03bcba93d1db79edbff"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ee57b89e5da9fffbe0d26647e4ff0750dacb9943"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/35461d23744175a78b6280293892cca357c22793"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/bdff76dff6ec23d6fe35812fa33e5c4ce2cdb770"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/a9a39233ec1fc9f97ea1340a4d09bb7ec2be5153"
    }
  ],
  "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": 8.1,
      "cvss_v3_severity": "High",
      "scenario": "AV:A - Exploitation requires injecting a crafted FPIN ELS frame onto the Fibre Channel fabric from an adjacent fabric actor (compromised switch, fabric controller, or same-zone N_Port), not via IP or local syscalls.\nAC:L - Once on the fabric, an attacker can reliably trigger the bug by sending an FPIN with a Link-Integrity or Peer-Congestion descriptor containing pname_count=256 and a minimally valid TLV length; no race or special memory layout is required.\nPR:N - The attacker needs no privileges on the victim Linux host; FPIN ELS frames are processed without authentication once the HBA has completed fabric discovery.\nUI:N - No victim user action is required; the malicious FPIN is processed automatically when received by the HBA firmware and driver stack.\nS:U - Impact is confined to kernel availability and information disclosure on the affected host; it does not cross a security boundary such as VM escape or sandbox breakout.\nC:H - The unbounded loop reads pname_list[i] beyond the validated descriptor body via out-of-bounds kernel memory reads on every iteration, enabling information disclosure from adjacent kernel memory.\nI:N - The bug causes only counter increments in FPIN statistics structures on matched rports; there is no memory corruption or write primitive that could modify arbitrary data or achieve code execution.\nA:H - The infinite loop pins a CPU in kernel context (potentially from interrupt/DPC paths) and repeatedly acquires host_lock via fc_find_rport_by_wwpn(), causing soft lockup and complete loss of host availability."
    }
  }
}