{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-97957",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-97957"
  ],
  "published": "2026-09-25T10:24:31Z",
  "summary": "net: hinic: fix mailbox segment buffer overflow",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: hinic: fix mailbox segment buffer overflow\n\ncheck_mbox_seq_id_and_seg_len() validates that seq_id does not\nexceed SEQ_ID_MAX_VAL (42) and seg_len does not exceed\nMBOX_SEG_LEN (48).  However, this allows the last segment\n(seq_id=42) to carry a full 48-byte payload, writing to offset\n42*48=2016 for 48 bytes (ending at byte 2064).  The receive\nbuffer is only MBOX_MAX_BUF_SZ (2048) bytes, resulting in a\n16-byte heap buffer overflow.\n\nThe hinic3 driver already handles this correctly by defining\nMBOX_LAST_SEG_MAX_LEN and rejecting the last segment when it\nexceeds the remaining buffer space.  Apply the same fix to the\nhinic driver.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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": "6.1.189",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-97957"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/7cc974799fde846eda2d8f00ad4f8e1810eb0499"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8de1e23bd91fe3a6683e4bc574e2d6bcb0eef920"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/72be1fd5d256dde748c0905c5e1749a119cad5bd"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c622bbc212207d7c6bbd69dd88f0c3a3f5853d16"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/eca54a092d5f7b497b458ff5a6f66d4f7bfb6674"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9f6ad383901d0cb1c8ea5f7f3160fabfe1540eb5"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/513f7b16ed0cffae9348151c72bed17c7073096f"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/5d4d985957434867bbe85e4fa5e638f3e48ad522"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-10-03T11:04:09Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 8.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The malformed input is a mailbox header (SEQID/SEG_LEN) and 48-byte body that a VF driver writes into its own mailbox registers. The hardware delivers it to the PF's hinic_mbox_func_aeqe_handler() -> recv_mbox_handler(). The attacker is code running in a guest that owns an SR-IOV VF (or a local driver), not a remote network peer, so this is local access.\nAC:L - The attacker sends segments seq_id 0..42 in order, each with seg_len=48. check_mbox_seq_id_and_seg_len() accepts all of them, and the memcpy at offset 42*48 overflows every time. The only setup is a VF assigned to the attacker's VM, which is the standard SR-IOV passthrough deployment. Nothing depends on timing or state outside the attacker's control.\nPR:L - Writing raw mailbox headers needs kernel control of the VF, i.e. root inside the guest. A VM tenant always has that, and it gives no privilege on the host whose PF driver is corrupted. The random id checked by check_vf_mbox_random_id() is given to every genuine VF, so it does not stop a hostile VF driver.\nUI:N - The PF host processes the mailbox message on its own from the AEQ handler. Nobody on the host has to do anything.\nS:C - The bug is in a guest-controlled VF's messages, but the overflow corrupts the host kernel heap in the PF driver (recv_mbox->mbox, kzalloc(2048)). That crosses the guest-to-host boundary, like a VM escape.\nC:H - Overwriting the first 16 bytes of the neighbouring kmalloc-2048 object with attacker-chosen data can corrupt pointers or length fields in that object. That is a normal route to reading arbitrary host kernel memory.\nI:H - recv_mbox_handler() copies 16 attacker-chosen bytes from the mailbox body past the end of the 2048-byte receive buffer. This is a controlled heap out-of-bounds write in the host kernel, which can lead to control-flow hijack.\nA:H - The guest can repeat the corruption of the neighbouring host heap object at will, crashing or panicking the host kernel. That takes down every tenant on the host."
    }
  }
}