{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "4d79dba0e00749fa40de8ef13a9b85ce57a1603b"
            },
            {
              "fixed": "e5964064e3fbe6325893408faff08ca33de0e2c3"
            },
            {
              "fixed": "96751028c0d4dec785709ea3eb0ab38a4f2ded96"
            },
            {
              "fixed": "1d3b24b16a0b013792e8f1e3ed060f0b46f537d1"
            },
            {
              "fixed": "d9d7eeb0cea5b55b82888f443622fd8d4ee064f3"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0"
            },
            {
              "fixed": "6.12.111"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.53"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97564.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: reject userspace cifs.idmap descriptions\n\ncifs.idmap key descriptions carry authority-bearing fields (owner and\ngroup SIDs and uid/gid values in \"os:\"/\"gs:\"/\"oi:\"/\"gi:\" form) that the\ncifs.idmap upcall helper treats as kernel-originating inputs.  Unlike\nits sibling cifs.spnego, the cifs.idmap key type has no vet_description\nhook, so userspace can create keys of this type through\nrequest_key(2)/add_key(2) and supply those fields without CIFS origin.\nA request_key(2) call with a non-NULL callout then drives a root\nusermodehelper upcall (/sbin/request-key -\u003e cifs.idmap) that consumes\nthe unvetted description in root context.\n\nOnly accept cifs.idmap descriptions while CIFS is using its private\nroot_cred to request the key.  id_to_sid()/sid_to_id() already run\nunder override_creds(root_cred), so the kernel-originated path is\nunaffected.\n\nThis mirrors commit 3da1fdf4efbc (\"smb: client: reject userspace\ncifs.spnego descriptions\"), which applied the same restriction to\ncifs.spnego.",
  "id": "CVE-2026-97564",
  "modified": "2026-09-27T03:30:29.899703Z",
  "published": "2026-09-25T10:21:51.858Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1d3b24b16a0b013792e8f1e3ed060f0b46f537d1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/96751028c0d4dec785709ea3eb0ab38a4f2ded96"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d9d7eeb0cea5b55b82888f443622fd8d4ee064f3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e5964064e3fbe6325893408faff08ca33de0e2c3"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97564.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-97564"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "smb: client: reject userspace cifs.idmap descriptions"
}