{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c"
            },
            {
              "fixed": "ee5588e2bc41acb73f6676c0520420c107cd0140"
            },
            {
              "fixed": "86f7060cd638d6eb042e8ed780fb83a59ca0dcb3"
            },
            {
              "fixed": "5f2806684b05bd24d05c091083b8e2517ba8ffac"
            },
            {
              "fixed": "b268984ae88cb0dcd7a8e8263962c748448e26e8"
            },
            {
              "fixed": "ba0a4df8c563536857dcbf7b4dbd0f2a15f57ace"
            },
            {
              "fixed": "08bc6173fd611ad5a40f472bf5f15b92aea0fe40"
            },
            {
              "fixed": "770444611f047dbfd4517ec0bc1b179d40c2f346"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.203"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.167"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.130"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.78"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.19"
            }
          ],
          "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-2026-43405.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: Use u32 for non-negative values in ceph_monmap_decode()\n\nThis patch fixes unnecessary implicit conversions that change signedness\nof blob_len and num_mon in ceph_monmap_decode().\nCurrently blob_len and num_mon are (signed) int variables. They are used\nto hold values that are always non-negative and get assigned in\nceph_decode_32_safe(), which is meant to assign u32 values. Both\nvariables are subsequently used as unsigned values, and the value of\nnum_mon is further assigned to monmap-\u003enum_mon, which is of type u32.\nTherefore, both variables should be of type u32. This is especially\nrelevant for num_mon. If the value read from the incoming message is\nvery large, it is interpreted as a negative value, and the check for\nnum_mon \u003e CEPH_MAX_MON does not catch it. This leads to the attempt to\nallocate a very large chunk of memory for monmap, which will most likely\nfail. In this case, an unnecessary attempt to allocate memory is\nperformed, and -ENOMEM is returned instead of -EINVAL.",
  "id": "CVE-2026-43405",
  "modified": "2026-07-15T01:49:09.037903793Z",
  "published": "2026-05-08T14:21:45.581Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/08bc6173fd611ad5a40f472bf5f15b92aea0fe40"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5f2806684b05bd24d05c091083b8e2517ba8ffac"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/770444611f047dbfd4517ec0bc1b179d40c2f346"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/86f7060cd638d6eb042e8ed780fb83a59ca0dcb3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b268984ae88cb0dcd7a8e8263962c748448e26e8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ba0a4df8c563536857dcbf7b4dbd0f2a15f57ace"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ee5588e2bc41acb73f6676c0520420c107cd0140"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43405.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43405"
    },
    {
      "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:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "libceph: Use u32 for non-negative values in ceph_monmap_decode()"
}