{
  "id": "CVE-2026-98366",
  "url": "https://spydr.io/cve/CVE-2026-98366",
  "published": "2026-10-06T09:18:30.823Z",
  "modified": "2026-10-06T09:18:30.823Z",
  "score": null,
  "severity": null,
  "cvss_version": null,
  "vector": null,
  "score_source": null,
  "epss": 0.00156,
  "epss_percentile": 0.04155,
  "exploited": false,
  "kev": null,
  "ssvc_exploitation": null,
  "vendors": [
    "Linux"
  ],
  "products": [
    "Linux"
  ],
  "cwes": [],
  "description": "In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: validate access flags before swapping the MR's PD rxe_rereg_user_mr() reassigns mr->ibmr.pd first and only then validates the IB_MR_REREG_ACCESS argument: if (flags & IB_MR_REREG_PD) { rxe_put(old_pd); rxe_get(pd); mr->ibmr.pd = ibpd; } if (flags & IB_MR_REREG_ACCESS) { if (access & ~RXE_ACCESS_SUPPORTED_MR) return ERR_PTR(-EOPNOTSUPP); mr->access = access; } Both flags pass the entry check because RXE_MR_REREG_SUPPORTED is IB_MR_REREG_PD | IB_MR_REREG_ACCESS, so a caller can reach the access check with mr->ibmr.pd already reassigned. mr->ibmr.pd is owned by the core, which adjusts pd->usecnt only on the success path: ib_uverbs_rereg_mr() jumps to put_new_uobj on a driver error without undoing the reassignment, so mr->pd == new_pd while the usecnts still charge the MR to orig_pd. ib_dereg_mr_user() then decrements new_pd, whose count can reach zero while a memory window still references it; uverbs_free_pd() frees the PD on that count alone and rxe_mw_cleanup() writes to freed memory: BUG: KASAN: slab-use-after-free in __rxe_put+0x31/0xa0 Write of size 4 at addr ffff8881301dd690 by task rxe_poc/591 __rxe_put+0x31/0xa0 rxe_mw_cleanup+0x42/0x200 __rxe_cleanup+0x115/0x370 rxe_dealloc_mw+0x4c/0x80 Allocated by task 591: ib_uverbs_alloc_pd+0x258/0x540 Freed by task 591: ib_dealloc_pd_user+0x174/0x210 uverbs_free_pd+0x8d/0xc0 ib_uverbs_dealloc_pd+0x18e/0x1d0 Validate the access flags before mutating any state so the callback either applies every requested change or none.",
  "status": "Received",
  "score_type": null,
  "scores": {
    "cvss_v40": null,
    "cvss_v31": null,
    "cvss_v30": null
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/08f12745cb72981aa2cabe214af0c7a42a856f0a",
      "tags": []
    },
    {
      "url": "https://git.kernel.org/stable/c/4dd7a53f1c5b44693c26dac4b9b5bd5bb9d604c8",
      "tags": []
    },
    {
      "url": "https://git.kernel.org/stable/c/7230cc456d4bb2221c20c5f1d22b38b8576aa16f",
      "tags": []
    },
    {
      "url": "https://git.kernel.org/stable/c/ae36a5b609ae79f4de966328b78d2584be9719a4",
      "tags": []
    },
    {
      "url": "https://git.kernel.org/stable/c/fe602c91a52e161ace4afd5bdb8f33270c554c6f",
      "tags": []
    }
  ],
  "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98366",
  "covered_in": [],
  "attribution": [
    {
      "source": "NVD",
      "url": "https://nvd.nist.gov",
      "notice": "This product uses data from the NVD API but is not endorsed or certified by the NVD."
    },
    {
      "source": "CISA KEV",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "notice": "Known exploited vulnerabilities from the CISA KEV catalog."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss",
      "notice": "Exploit prediction scores from FIRST EPSS."
    }
  ]
}