{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "ee4af50ca94f58afc3532662779b9cf80bbe27c8"
            },
            {
              "fixed": "ad3c0c4400686f6f37b382aaa48fac2b9aefccbe"
            },
            {
              "fixed": "68013a9bd4c01acd42073715f00e1a1992f089ee"
            },
            {
              "fixed": "e8474cfbac9ada2cdaa4eaedec22aadfa0f58559"
            },
            {
              "fixed": "058b451b1039f056d1362c4fec2229e522366ab0"
            },
            {
              "fixed": "b5597bb83fc37b5b5da74a4453fa920b932cf39a"
            },
            {
              "fixed": "08fa5d818e5bf53c7ca234d88ba334f32004e9b6"
            },
            {
              "fixed": "08841b06fa64d8edbd1a21ca6e613420c90cc4b8"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "7f401f160a9c7a1ff84ba3cb9b2f636d1f5cfb6b"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.18.7"
            },
            {
              "fixed": "4.19"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.19.0"
            },
            {
              "fixed": "5.10.259"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.210"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.176"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.140"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.88"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "7.0.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45991.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nudf: fix partition descriptor append bookkeeping\n\nMounting a crafted UDF image with repeated partition descriptors can\ntrigger a heap out-of-bounds write in part_descs_loc[].\n\nhandle_partition_descriptor() deduplicates entries by partition number,\nbut appended slots never record partnum. As a result duplicate\nPartition Descriptors are appended repeatedly and num_part_descs keeps\ngrowing.\n\nOnce the table is full, the growth path still sizes the allocation from\npartnum even though inserts are indexed by num_part_descs. If partnum is\nalready aligned to PART_DESC_ALLOC_STEP, ALIGN(partnum, step) can keep\nthe old capacity and the next append writes past the end of the table.\n\nStore partnum in the appended slot and size growth from the next append\ncount so deduplication and capacity tracking follow the same model.",
  "id": "CVE-2026-45991",
  "modified": "2026-07-08T05:37:23.844689521Z",
  "published": "2026-05-27T12:55:43.449Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/058b451b1039f056d1362c4fec2229e522366ab0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/08841b06fa64d8edbd1a21ca6e613420c90cc4b8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/08fa5d818e5bf53c7ca234d88ba334f32004e9b6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/68013a9bd4c01acd42073715f00e1a1992f089ee"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ad3c0c4400686f6f37b382aaa48fac2b9aefccbe"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b5597bb83fc37b5b5da74a4453fa920b932cf39a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e8474cfbac9ada2cdaa4eaedec22aadfa0f58559"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45991.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45991"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "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": "udf: fix partition descriptor append bookkeeping"
}