{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-74377",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-74377"
  ],
  "published": "2026-08-15T06:04:33Z",
  "summary": "RDMA/rxe: Copy WQE to local buffer in non-SRQ receive path",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Copy WQE to local buffer in non-SRQ receive path\n\nFor non-SRQ QPs, the responder reads WQE fields directly from the\nshared queue buffer mapped into userspace. This allows a malicious\nuser to modify fields like num_sge or sge entries while the kernel\nis processing the WQE, leading to out-of-bounds reads in\nrxe_resp_check_length() and copy_data().\n\nIntroduce get_recv_wqe() that validates num_sge and copies the WQE\nto a kernel-local buffer before processing, matching the approach\nalready used for SRQ WQEs in get_srq_wqe(). The srq_wqe buffer is\nreused since SRQ and non-SRQ paths are mutually exclusive per QP.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/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": "6.1.178",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-74377"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/2e60378fb3c8b51c94103bb40014c4fe38fa5033"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/fc72fd61cc8b2e2e3e92ae4c0e9cc30c9a7ecb78"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9fa785137303f7109c23dea779b8dedc67c9b531"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/5420eebf3b3c162bfaf965f30e61cd1d689e5732"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/a211b7904aed365e4e4f08a48ec6e6dd1ea7b16b"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d6ab440240a04b8737ee4c7bb21af9182e451733"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-17T05:50:24Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:L - Exploitation requires mutating mmap'd receive WQEs through /dev/infiniband/uverbs; inbound RoCE packets (rxe_udp_encap_recv\u2192rxe_rcv\u2192rxe_receiver) only trigger processing and cannot alter WQE fields without local control of the userspace-mapped receive queue.\nAC:L - The attacker controls both sides of the TOCTOU\u2014userspace threads racing num_sge/sge edits while posting recv WRs and driving inbound RoCE SEND/WRITE traffic\u2014so out-of-bounds reads in rxe_resp_check_length() and copy_data() are reliably triggerable with retries.\nPR:L - uverbs_devnode() publishes /dev/infiniband/uverbsN as mode 0666, letting any local account create userspace QPs and mmap receive queues; rxe link setup needs CAP_NET_ADMIN obtainable in a user+network namespace via unshare -Urn, matching PR:L kernel guidance.\nUI:N - Exploitation is entirely self-driven from the attacker's own RDMA verbs client and concurrent userspace threads; no victim user action, mount, or file open is required.\nS:U - Impact is kernel memory corruption and local privilege escalation within the host kernel security authority, not a VM guest-to-host escape, IOMMU/DMA boundary bypass, or other cross-scope compromise.\nC:H - Inflating num_sge or rewriting sge entries during processing causes out-of-bounds reads in rxe_resp_check_length() and copy_data() beyond the allocated WQE slot, potentially into adjacent vmalloc/kernel memory, enabling arbitrary kernel information disclosure.\nI:H - copy_data() walks attacker-forged out-of-bounds sge entries and performs rxe_mr_copy writes of incoming RDMA payload into MR-backed memory; combined with queue overruns this yields controlled memory corruption exploitable for arbitrary write and code execution.\nA:H - Processing a WQE with an attacker-inflated num_sge causes the kernel to walk far past valid sge slots, dereferencing invalid pointers and corrupting memory, reliably producing kernel oops/panic and total loss of availability."
    }
  }
}