CVE-2026-23405 (GCVE-0-2026-23405)
Vulnerability from cvelistv5
Published
2026-04-01 08:36
Modified
2026-04-18 08:58
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix: limit the number of levels of policy namespaces Currently the number of policy namespaces is not bounded relying on the user namespace limit. However policy namespaces aren't strictly tied to user namespaces and it is possible to create them and nest them arbitrarily deep which can be used to exhaust system resource. Hard cap policy namespaces to the same depth as user namespaces.
References
Impacted products
Vendor Product Version
Linux Linux Version: c88d4c7b049e87998ac0a9f455aa545cc895ef92
Version: c88d4c7b049e87998ac0a9f455aa545cc895ef92
Version: c88d4c7b049e87998ac0a9f455aa545cc895ef92
Version: c88d4c7b049e87998ac0a9f455aa545cc895ef92
Version: c88d4c7b049e87998ac0a9f455aa545cc895ef92
Version: c88d4c7b049e87998ac0a9f455aa545cc895ef92
Version: c88d4c7b049e87998ac0a9f455aa545cc895ef92
Version: c88d4c7b049e87998ac0a9f455aa545cc895ef92
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{
  "containers": {
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          "defaultStatus": "unaffected",
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          "programFiles": [
            "security/apparmor/include/policy_ns.h",
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      "cpeApplicability": [
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              "operator": "OR"
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      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix: limit the number of levels of policy namespaces\n\nCurrently the number of policy namespaces is not bounded relying on\nthe user namespace limit. However policy namespaces aren\u0027t strictly\ntied to user namespaces and it is possible to create them and nest\nthem arbitrarily deep which can be used to exhaust system resource.\n\nHard cap policy namespaces to the same depth as user namespaces."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-18T08:58:39.212Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
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          "url": "https://git.kernel.org/stable/c/6b396cc2f0365e684fc1d3547d18ef79fcee225d"
        },
        {
          "url": "https://git.kernel.org/stable/c/87d0cecc900e55d55fc4dbfb43ac93e269c7a5b3"
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        },
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          "url": "https://git.kernel.org/stable/c/3f8699b3ee0c04b4b9bc27b82cd89a40e81e1d2e"
        },
        {
          "url": "https://git.kernel.org/stable/c/853ce31ca72097d23991a06876a2ccb5cb64b603"
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        {
          "url": "https://git.kernel.org/stable/c/d42b2b6bb77ca40ee34ab74ad79305840b5f315d"
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          "url": "https://git.kernel.org/stable/c/7b6495ead2c611647f6b11441a852324e3eb8616"
        },
        {
          "url": "https://git.kernel.org/stable/c/306039414932c80f8420695a24d4fe10c84ccfb2"
        }
      ],
      "title": "apparmor: fix: limit the number of levels of policy namespaces",
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  "cveMetadata": {
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-23405",
    "datePublished": "2026-04-01T08:36:35.697Z",
    "dateReserved": "2026-01-13T15:37:46.012Z",
    "dateUpdated": "2026-04-18T08:58:39.212Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


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