{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-74296",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-74296"
  ],
  "published": "2026-08-15T06:04:33Z",
  "summary": "RDMA/mlx5: Release the HW\u2011provided UAR index rather than the SW one",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/mlx5: Release the HW\u2011provided UAR index rather than the SW one\n\nFree the UAR index returned by the hardware.",
  "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-2026-74296"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/80f1f49f53a42733e60c90e0ec545e647969214d"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/aabfc845838ef453f1d22d7665596f9cc48be7dd"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/6f83de384ca582fa87b4c2b0d03bd1ed3bf9a2ee"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d3ff718c0c7153e2641e6a09507bace14fc5c402"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ef369446f62903ea079e8a7954b5bf8bb8300fe3"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/449ae7927152e46acbe5f19f97eafdae6d3a96b1"
    }
  ],
  "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 a local mmap(2) on an opened mlx5 uverbs file descriptor (/dev/infiniband/uverbs*); the bug is in uar_mmap() error cleanup and is not reachable via remote RDMA/network packet handling.\nAC:L - An attacker who can open uverbs and issue MLX5_IB_MMAP_ALLOC_WC can reliably reach the faulty cleanup by forcing rdma_user_mmap_io()/io_remap_pfn_range() to fail (e.g., memory or VMA map pressure), and controls all syscall parameters for the race-free trigger.\nPR:L - Any unprivileged local user with access to the mlx5 RDMA character device (default 0666 uverbs nodes on shared HPC/cloud compute nodes with ConnectX NICs) can alloc a context and mmap; no real-root or CAP_SYS_ADMIN capability is required.\nUI:N - Exploitation is fully attacker-driven through uverbs open, alloc_ucontext, and mmap syscalls; no victim interaction such as mounting filesystems or opening files is needed.\nS:U - Impact is confined to kernel/driver and RDMA device resource integrity on the host; it does not cross a VM-hypervisor or IOMMU security boundary into a different authority.\nC:H - Deallocating the wrong hardware UAR index frees another context's live UAR while the attacker-allocated UAR leaks, creating a cross-context UAR use-after-free that can expose other users' MMIO doorbell/register mappings and device state.\nI:H - UAR pages provide userspace MMIO write access to mlx5 doorbells and control registers; corrupting or reassigning UAR ownership enables arbitrary device register/DMA manipulation and is exploitable for privilege escalation beyond simple data tampering.\nA:H - Freeing an in-use hardware UAR from another context can cause kernel oops/panic, NIC hangs, or repeated crashes when victims continue doorbell/MMIO access through stale mappings."
    }
  }
}