{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "a1d220d9dafa8d76ba60a784a1016c3134e6a1e8"
            },
            {
              "fixed": "3376b345df155ca36d8611857b41ff7d5183fc38"
            },
            {
              "fixed": "2f3dea284c761c890d676f77d5e55c0c496b4ef4"
            },
            {
              "fixed": "0ad650e60150eda789deca5e78a6a09d26bf8fc9"
            },
            {
              "fixed": "e6b899f08066e744f89df16ceb782e06868bd148"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.12.0"
            },
            {
              "fixed": "6.12.78"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.20"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43403.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnsfs: tighten permission checks for ns iteration ioctls\n\nEven privileged services should not necessarily be able to see other\nprivileged service's namespaces so they can't leak information to each\nother. Use may_see_all_namespaces() helper that centralizes this policy\nuntil the nstree adapts.",
  "id": "CVE-2026-43403",
  "modified": "2026-07-15T01:49:19.331044855Z",
  "published": "2026-05-08T14:21:44.204Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0ad650e60150eda789deca5e78a6a09d26bf8fc9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2f3dea284c761c890d676f77d5e55c0c496b4ef4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3376b345df155ca36d8611857b41ff7d5183fc38"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e6b899f08066e744f89df16ceb782e06868bd148"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43403.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43403"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "nsfs: tighten permission checks for ns iteration ioctls"
}