{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/accel/qaic/qaic_control.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "57d14cb3bae4619ce2fb5235cb318c3d5d8f53fd",
              "status": "affected",
              "version": "129776ac2e38231fa9c02ce20e116c99de291666",
              "versionType": "git"
            },
            {
              "lessThan": "51b56382ed2a2b03347372272362b3baa623ed1e",
              "status": "affected",
              "version": "129776ac2e38231fa9c02ce20e116c99de291666",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/accel/qaic/qaic_control.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.4"
            },
            {
              "lessThan": "6.4",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.4.*",
              "status": "unaffected",
              "version": "6.4.7",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.5",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.4.7",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.5",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\naccel/qaic: tighten bounds checking in decode_message()\n\nCopy the bounds checking from encode_message() to decode_message().\n\nThis patch addresses the following concerns.  Ensure that there is\nenough space for at least one header so that we don\u0027t have a negative\nsize later.\n\n\tif (msg_hdr_len \u003c sizeof(*trans_hdr))\n\nEnsure that we have enough space to read the next header from the\nmsg-\u003edata.\n\n\tif (msg_len \u003e msg_hdr_len - sizeof(*trans_hdr))\n\t\treturn -EINVAL;\n\nCheck that the trans_hdr-\u003elen is not below the minimum size:\n\n\tif (hdr_len \u003c sizeof(*trans_hdr))\n\nThis minimum check ensures that we don\u0027t corrupt memory in\ndecode_passthrough() when we do.\n\n\tmemcpy(out_trans-\u003edata, in_trans-\u003edata, len - sizeof(in_trans-\u003ehdr));\n\nAnd finally, use size_add() to prevent an integer overflow:\n\n\tif (size_add(msg_len, hdr_len) \u003e msg_hdr_len)"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.4,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The malicious input is the MHI control-channel response emitted by the attached Qualcomm Cloud AI 100 PCIe/M.2 accelerator, so the attack originates from locally-attached hardware or firmware-compromised on-card QSM (the card executes untrusted tenant model workloads in cloud AI deployments), not from any network. This matches the kernel CNA precedent for analogous MHI host-driver bugs (CVE-2023-53598, CVE-2025-39790).\nAC:L - The device has complete, deterministic control over every byte of the response \u2014 magic number, sequence number, `hdr.len`, `hdr.count`, and each `wire_trans_hdr` \u2014 and `decode_message()` consumes it unconditionally; setting `trans_hdr-\u003etype = QAIC_TRANS_PASSTHROUGH_FROM_DEV` with `len = 0` reliably reaches the underflowed `memcpy()` every time, with no race, no timing window, and no memory-layout condition outside the attacker\u0027s influence.\nPR:N - No host account, credential, or capability is needed: `qaic_mhi_probe()` invokes `get_cntl_version()` \u2192 `decode_message()` automatically at device power-up, and `qaic_control_open()` installs `valid_crc_stub` so that first response\u0027s CRC is not even validated. A compromised device can also force re-entry by triggering an MHI SYS_ERROR/reset; on the user-driven path the `QAIC_MANAGE` ioctl carries flags `0` (no `DRM_ROOT_ONLY`, no `DRM_AUTH`), so an unprivileged holder of `/dev/accel/accelN` suffices.\nUI:N - The vulnerable decode runs from the MHI probe path and the control-response workqueue with no victim action required \u2014 no mount, no file open, no administrator step. Device enumeration and driver bring-up alone execute the parser.\nS:U - The out-of-bounds read and the unbounded `memcpy()` write both land in the host kernel\u0027s own heap, the same security authority as the vulnerable driver. No hypervisor, IOMMU, or sandbox boundary is crossed by the corruption itself.\nC:H - Without the `msg_len \u003e msg_hdr_len - sizeof(*trans_hdr)` guard, `trans_hdr` is read past the end of the 4 KB `kmalloc()`\u0027d (not zeroed) response buffer, and `decode_passthrough()` copies out-of-bounds source bytes into `user_msg-\u003edata`, which `qaic_manage_ioctl()` hands straight back via `copy_to_user()` \u2014 a direct kernel-heap disclosure primitive. The same underflowed copy also reads far beyond the source buffer.\nI:H - `memcpy(out_trans-\u003edata, in_trans-\u003edata, len - sizeof(in_trans-\u003ehdr))` with a device-supplied `len \u003c 8` produces a size of ~2^64, giving an out-of-bounds heap write whose source contents are entirely device-controlled, into a destination that in the probe path is a ~32-byte allocation. That is a fully controlled slab overflow suitable for adjacent-object corruption and control-flow hijack.\nA:H - The underflowed `memcpy()` walks off the end of the slab and past the mapped heap, guaranteeing slab corruption, an oops, and a kernel panic; the missing `hdr_len` minimum also permits a zero-advance transaction loop. The attacking device can repeat this on every probe or reset, denying service permanently."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T09:14:25.393Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/57d14cb3bae4619ce2fb5235cb318c3d5d8f53fd"
        },
        {
          "url": "https://git.kernel.org/stable/c/51b56382ed2a2b03347372272362b3baa623ed1e"
        }
      ],
      "title": "accel/qaic: tighten bounds checking in decode_message()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2023-53493",
    "datePublished": "2025-10-01T11:45:44.939Z",
    "dateReserved": "2025-10-01T11:39:39.403Z",
    "dateUpdated": "2026-08-05T09:14:25.393Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}