{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2025-38375",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2025-38375"
  ],
  "published": "2025-07-25T12:55:41Z",
  "summary": "virtio-net: ensure the received length does not exceed allocated size",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio-net: ensure the received length does not exceed allocated size\n\nIn xdp_linearize_page, when reading the following buffers from the ring,\nwe forget to check the received length with the true allocate size. This\ncan lead to an out-of-bound read. This commit adds that missing check.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/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": "6.1.144",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-38375"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/773e95c268b5d859f51f7547559734fd2a57660c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ddc8649d363141fb3371dd81a73e1cb4ef8ed1e1"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/982beb7582c193544eb9c6083937ec5ac1c9d651"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/6aca3dad2145e864dfe4d1060f45eb1bac75dd58"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/80b971be4c37a4d23a7f1abc5ff33dc7733d649b"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/bc68bc3563344ccdc57d1961457cdeecab8f81ef"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/11f2d0e8be2b5e784ac45fa3da226492c3e506d8"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/315dbdd7cdf6aa533829774caaf4d25f1fd20e73"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-05T12:19:11Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 8.4,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - The attacker-controlled value is the used-ring length written by the virtio backend (hypervisor/VMM, vhost-user daemon, VDUSE device, or vDPA hardware), not anything carried in received network packets, so a remote peer cannot reach it. The attack is delivered over the local paravirtual transport, matching kernel CNA precedent for virtio device-supplied-length bugs (CVE-2026-64456, CVE-2026-46123).\nAC:L - The backend fully and deterministically controls both `hdr->num_buffers` and the used-ring `len`, with no race to win and no memory-layout guessing required; a single crafted RX completion triggers it every time. XDP attachment is a target configuration the backend can observe via the guest's headroom/GSO renegotiation, not an uncontrollable condition.\nPR:N - The malicious backend needs no credentials, account, or capability inside the victim guest \u2014 it simply completes a receive buffer with a bogus length. This matches the PR:N scoring used for the equivalent virtio_bt and hwrng-virtio device-length CVEs.\nUI:N - Triggering requires only that the driver process an RX completion in NAPI/softirq context, which happens automatically. No victim action of any kind is needed.\nS:U - The vulnerable component and the impacted component are both the virtio_net driver's own kernel, and a host-to-guest attack does not gain the attacker authority it did not already hold. This is not a guest-to-host escape or an IOMMU/DMA boundary bypass.\nC:H - Each malformed completion copies up to ~3.5 KB of adjacent kernel memory into the linearized packet, which the XDP program can then XDP_TX/XDP_REDIRECT back to the attacker or which reaches userspace via a socket, giving a repeatable kernel memory disclosure channel. The integer-overflow variant extends the read arbitrarily far past the source buffer.\nI:H - The `page_off + buflen + tailroom > PAGE_SIZE` guard is defeated by unsigned wraparound (verified: `buflen = 0xFFFFFD5C` makes the sum evaluate to 0), so the memcpy writes gigabytes beyond the single-page destination, corrupting arbitrary kernel heap memory. That is an out-of-bounds write, not merely the out-of-bounds read named in the commit message.\nA:H - Reading past the end of the source page, or the multi-gigabyte memcpy from the overflow variant, faults in softirq context and oopses/panics the kernel, and is instantly reproducible under KASAN or DEBUG_PAGEALLOC. The wholesale kernel memory corruption makes a crash the expected outcome."
    }
  }
}