{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.94-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.0.12-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  memfd: deny writeable mappings when implying SEAL_WRITE  When SEAL_EXEC is added, SEAL_WRITE is implied to make W^X.  But the implied seal is set after the check that makes sure the memfd can not have any writable mappings.  This means one can use SEAL_EXEC to apply SEAL_WRITE while having writeable mappings.  This breaks the contract that SEAL_WRITE provides and can be used by an attacker to pass a memfd that appears to be write sealed but can still be modified arbitrarily.  Fix this by adding the implied seals before the call for mapping_deny_writable() is done.",
  "id": "DEBIAN-CVE-2026-63952",
  "modified": "2026-10-01T02:47:51.804214799Z",
  "published": "2026-07-19T16:17:13.950Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-63952"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-63952"
  ]
}