{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  smb: client: reject userspace cifs.idmap descriptions  cifs.idmap key descriptions carry authority-bearing fields (owner and group SIDs and uid/gid values in \"os:\"/\"gs:\"/\"oi:\"/\"gi:\" form) that the cifs.idmap upcall helper treats as kernel-originating inputs.  Unlike its sibling cifs.spnego, the cifs.idmap key type has no vet_description hook, so userspace can create keys of this type through request_key(2)/add_key(2) and supply those fields without CIFS origin. A request_key(2) call with a non-NULL callout then drives a root usermodehelper upcall (/sbin/request-key -\u003e cifs.idmap) that consumes the unvetted description in root context.  Only accept cifs.idmap descriptions while CIFS is using its private root_cred to request the key.  id_to_sid()/sid_to_id() already run under override_creds(root_cred), so the kernel-originated path is unaffected.  This mirrors commit 3da1fdf4efbc (\"smb: client: reject userspace cifs.spnego descriptions\"), which applied the same restriction to cifs.spnego.",
  "id": "DEBIAN-CVE-2026-97564",
  "modified": "2026-09-26T04:47:40.454679966Z",
  "published": "2026-09-25T11:17:07.007Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-97564"
    }
  ],
  "upstream": [
    "CVE-2026-97564"
  ]
}