accel/amdxdna: Disable device buffer exporting

{
  "id": "95fc67846cdf4875507712707ec762b8237582aaff2af0625704c4c59b1d2b5a",
  "url": "https://www.cve.org/CVERecord?id=CVE-2026-98436",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "accel/amdxdna: Disable device buffer exporting",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: accel/amdxdna: Disable device buffer exporting Device buffers are never intended to be exported. Disable exporting support explicitly.",
    "evidence": "cve:CVE-2026-98436",
    "products": [
      {
        "name": {
          "value": "Linux",
          "evidence": "/containers/cna/affected/0/product"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      },
      {
        "name": {
          "value": "Linux",
          "evidence": "/containers/cna/affected/1/product"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-98436",
      "aliases": [
        "CVE-2026-98436"
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "version": "3.1",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - A local DRM_IOCTL_AMDXDNA_CREATE_BO reaches amdxdna_drm_create_bo_ioctl()→amdxdna_drm_create_dev_bo(). PRIME_HANDLE_TO_FD then reaches the site fixed by amdxdna_gem_dev_obj_export(); without that callback, drm_gem_prime_handle_to_dmabuf() exports the object, with no remote input.\nAC:L - The attacker maps a DEV_HEAP, creates and exports an AMDXDNA_BO_DEV, closes the accel fd to free its amdxdna_client, then closes the retained dma-buf fd. This deterministic sequence requires no race or condition outside the attacker's control.\nPR:L - AMDXDNA_CREATE_BO is registered with flags 0, while PRIME_HANDLE_TO_FD has DRM_RENDER_ALLOW but no DRM_ROOT_ONLY or DRM_AUTH; drm_ioctl_permit() imposes no capability check. Only ordinary access to /dev/accel/accelN is required.\nUI:N - The attacker personally creates, maps, exports, and closes the buffer descriptors; no victim must open a file, mount media, or perform another action.\nS:U - The dangling amdxdna_client and its dev_heap_mm are kernel-owned objects corrupted within the host kernel's security authority; this path does not itself escape a VM or bypass an IOMMU boundary.\nC:H - After amdxdna_client_cleanup() frees abo->client, amdxdna_gem_heap_free() follows that stale pointer into dev_heap_mm and dev_heap_xa. Reclaiming the freed client allocation permits attacker-influenced pointer reads and the arbitrary-disclosure potential of a kernel UAF.\nI:H - amdxdna_gem_heap_free() locks the freed client->mm_lock and drm_mm_remove_node() performs tree/list updates through the freed dev_heap_mm. Heap grooming can control reclaimed pointer state, turning these writes into memory corruption and potential control-flow hijacking.\nA:H - Closing the retained dma-buf invokes drm_gem_dmabuf_release()→amdxdna_gem_dev_obj_free() and operates on the destroyed mutex and freed drm_mm state, which can immediately oops or panic the kernel."
            }
          ]
        }
      ],
      "affected": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "ac49797c1815d4f8f04b7053b2998c546283c89e",
              "lessThan": "33b00fa8023e8ade3409aa9c833b8ce65b8c29eb",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "ac49797c1815d4f8f04b7053b2998c546283c89e",
              "lessThan": "9480dd7ec3fcadd4217503e4bb32c16e19e4b21f",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "drivers/accel/amdxdna/amdxdna_gem.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.14"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "6.14",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "7.2.7",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "drivers/accel/amdxdna/amdxdna_gem.c"
          ],
          "defaultStatus": "affected"
        }
      ],
      "modified": "2026-10-26T06:55:45.188Z",
      "provider": "cve",
      "references": [
        "https://git.kernel.org/stable/c/33b00fa8023e8ade3409aa9c833b8ce65b8c29eb",
        "https://git.kernel.org/stable/c/9480dd7ec3fcadd4217503e4bb32c16e19e4b21f"
      ],
      "provider_metadata": {
        "cna": {
          "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "shortName": "Linux",
          "dateUpdated": "2026-10-26T06:55:45.188Z"
        }
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-98436",
        "evidence": "/cveMetadata/cveId"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/containers/cna/metrics"
  },
  "source_id": "core-cve",
  "document_id": 263322,
  "published_at": "2026-10-18T14:45:25.364+00:00"
}