{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "8700e3e7c4857d28ebaa824509934556da0b3e76"
            },
            {
              "fixed": "318787fa7193bd79691f2ebce4e80cb6abd0faef"
            },
            {
              "fixed": "6a79b1ea0fcb2c998fda6a793050f66146e9cc42"
            },
            {
              "fixed": "599cfdf44c1701c581cd4a21f1e1e03f8dc3840b"
            },
            {
              "fixed": "e3dc3a2fb05f4ed49c7f20594c4c52350d032189"
            },
            {
              "fixed": "f8ee926431a7bbec2b10c1290664af2cb290b983"
            },
            {
              "fixed": "006a3a5f75345c6a0dbf13fd3ee01406e93b6733"
            },
            {
              "fixed": "6fa18025e5782afff91415fd5217b39c1e4837d7"
            },
            {
              "fixed": "4c6f86d85d03cdb33addce86aa69aa795ca6c47a"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.8.0"
            },
            {
              "fixed": "5.10.258"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.209"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.175"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.140"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.88"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.30"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.0.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46133.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Reject unknown opcodes before ICRC processing\n\nEven after applying commit 7244491dab34 (\"RDMA/rxe: Validate pad and ICRC\nbefore payload_size() in rxe_rcv\"), a single unauthenticated UDP packet\ncan still trigger panic.  That patch handled payload_size() underflow only\nfor valid opcodes with short packets, not for packets carrying an unknown\nopcode.  The unknown-opcode OOB read described below predates that commit\nand reaches back to the initial Soft RoCE driver.\n\nThe check added there reads\n\n    pkt-\u003epaylen \u003c header_size(pkt) + bth_pad(pkt) + RXE_ICRC_SIZE\n\nwhere header_size(pkt) expands to rxe_opcode[pkt-\u003eopcode].length.  The\nrxe_opcode[] array has 256 entries but is only populated for defined IB\nopcodes; any other entry (for example opcode 0xff) is zero-initialized, so\nlength == 0 and the check degenerates to\n\n    pkt-\u003epaylen \u003c 0 + bth_pad(pkt) + RXE_ICRC_SIZE\n\nwhich does not constrain pkt-\u003epaylen enough.  rxe_icrc_hdr() then computes\n\n    rxe_opcode[pkt-\u003eopcode].length - RXE_BTH_BYTES\n\nwhich underflows when length == 0 and passes a huge value to rxe_crc32(),\ncausing an out-of-bounds read of the skb payload.\n\nReproduced on v7.0-rc7 with that fix applied, QEMU/KVM with\nCONFIG_RDMA_RXE=y and CONFIG_KASAN=y, after\n\n    rdma link add rxe0 type rxe netdev eth0\n\nA single 48-byte UDP packet to port 4791 with BTH opcode=0xff and\nQPN=IB_MULTICAST_QPN triggers:\n\n    BUG: KASAN: slab-out-of-bounds in crc32_le+0x115/0x170\n    Read of size 1 at addr ...\n    The buggy address is located 0 bytes to the right of\n     allocated 704-byte region\n    Call Trace:\n     crc32_le+0x115/0x170\n     rxe_icrc_hdr.isra.0+0x226/0x300\n     rxe_icrc_check+0x13f/0x3a0\n     rxe_rcv+0x6e1/0x16e0\n     rxe_udp_encap_recv+0x20a/0x320\n     udp_queue_rcv_one_skb+0x7ed/0x12c0\n\nSubsequent packets with the same shape fault on unmapped memory and panic\nthe kernel.  The trigger requires only module load and \"rdma link add\"; no\nQP, no connection, and no authentication.\n\nFix this by rejecting packets whose opcode has no rxe_opcode[] entry,\ndetected via the zero mask or zero length, before any length arithmetic\nruns.",
  "id": "CVE-2026-46133",
  "modified": "2026-07-08T05:36:15.947733802Z",
  "published": "2026-05-28T09:35:47.819Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/006a3a5f75345c6a0dbf13fd3ee01406e93b6733"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/318787fa7193bd79691f2ebce4e80cb6abd0faef"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4c6f86d85d03cdb33addce86aa69aa795ca6c47a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/599cfdf44c1701c581cd4a21f1e1e03f8dc3840b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6a79b1ea0fcb2c998fda6a793050f66146e9cc42"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6fa18025e5782afff91415fd5217b39c1e4837d7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e3dc3a2fb05f4ed49c7f20594c4c52350d032189"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f8ee926431a7bbec2b10c1290664af2cb290b983"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46133.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46133"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "RDMA/rxe: Reject unknown opcodes before ICRC processing"
}