{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-64018",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-64018"
  ],
  "published": "2026-07-19T15:41:06Z",
  "summary": "net: mana: validate rx_req_idx to prevent out-of-bounds array access",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: mana: validate rx_req_idx to prevent out-of-bounds array access\n\nIn mana_hwc_rx_event_handler(), rx_req_idx is derived from\nsge->address in DMA-coherent memory. In Confidential VMs\n(SEV-SNP/TDX), this memory is shared unencrypted and HW can modify\nWQE contents at any time. No bounds check exists on rx_req_idx,\nwhich can lead to an out-of-bounds access into reqs[].\n\nAdd bounds check on rx_req_idx in mana_hwc_rx_event_handler() before\nusing it to index the reqs[] array.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/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": "6.1.175",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-64018"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/5ddc715324badd7f2641bc177db1d027b402adae"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ff1d5af207bcea857d45fe81505f1bc4b29eaef0"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/01f7f893d5e1baae995beeb86cd0f3e6bb2a3b01"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/763a372d344fb12fae566d36ddb46e92454ad58c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/fa627a5eaa83fc0261f44ef3769693b886ca6e27"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/355e9f2b2a7887ca38100127989af3e422ba71d0"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/b809d0409991b75a6cff846a5ac27c3062953f84"
    }
  ],
  "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": 9.3,
      "cvss_v3_severity": "Critical",
      "scenario": "AV:L - The bug is reached via MSI-driven hardware completion processing in the MANA HWC control path (not netdev packet receive), triggered when the Azure hypervisor/host tampers with guest-visible DMA-coherent WQE memory on the same physical compute node.\nAC:L - A malicious host or NIC firmware that can modify shared unencrypted DMA buffers controls both the forged sge->address and the timing of HWC RX completions, allowing reliable out-of-bounds indexing without winning a race or depending on guest state.\nPR:N - Exploitation requires no privileges on the victim guest VM; the attacker operates from the Azure hypervisor/host side by modifying DMA-coherent memory that the guest kernel trusts during HWC response handling.\nUI:N - No victim user action is required; exploitation occurs automatically when the driver processes a hardware completion event on the HWC receive queue.\nS:C - In Confidential VMs the guest relies on host isolation guarantees, but shared unencrypted DMA memory lets a hostile hypervisor cross that CVM security boundary to corrupt guest kernel memory and confidentiality.\nC:H - An out-of-bounds rx_req_idx yields a corrupted hwc_work_request whose buf_va is dereferenced and copied via memcpy in mana_hwc_handle_resp(), enabling arbitrary kernel memory disclosure.\nI:H - The out-of-bounds hwc_work_request supplies attacker-controlled pointers and SGE fields used to repost RX WQEs via mana_hwc_post_rx_wqe(), enabling kernel heap corruption and exploitable memory writes.\nA:H - Indexing reqs[] out of bounds with attacker-controlled values can dereference invalid kernel pointers and corrupt adjacent heap objects, causing kernel oops/panic and denial of service."
    }
  }
}
