{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "087f997870a948820ec366701d178f402c6a23a3"
            },
            {
              "fixed": "c6a2706e08b8a1b2d3740161c0977d38e596c1ee"
            },
            {
              "fixed": "a69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3a"
            },
            {
              "fixed": "33503c083fda048c77903460ac0429e1e2c0e341"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.14.0"
            },
            {
              "fixed": "6.15.11"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.16.0"
            },
            {
              "fixed": "6.16.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39793.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/memmap: cast nr_pages to size_t before shifting\n\nIf the allocated size exceeds UINT_MAX, then it's necessary to cast\nthe mr-\u003enr_pages value to size_t to prevent it from overflowing. In\npractice this isn't much of a concern as the required memory size will\nhave been validated upfront, and accounted to the user. And \u003e 4GB sizes\nwill be necessary to make the lack of a cast a problem, which greatly\nexceeds normal user locked_vm settings that are generally in the kb to\nmb range. However, if root is used, then accounting isn't done, and\nthen it's possible to hit this issue.",
  "id": "CVE-2025-39793",
  "modified": "2026-08-12T03:51:35.199125283Z",
  "published": "2025-09-12T15:59:30.388Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/33503c083fda048c77903460ac0429e1e2c0e341"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c6a2706e08b8a1b2d3740161c0977d38e596c1ee"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/39xxx/CVE-2025-39793.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39793"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "io_uring/memmap: cast nr_pages to size_t before shifting"
}