{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "a63d4ac4ab6094c051a5a240260d16117a7a2f86"
            },
            {
              "fixed": "5f43d2c1bea280dcdfabaf156c25e7402fb8039f"
            },
            {
              "fixed": "92c43ac3c2b09eb16162e8144e73c00b7c3e29d6"
            },
            {
              "fixed": "6fc7da2a052f2825fff785e860e67183f5acaaba"
            },
            {
              "fixed": "01504da375f5b19df195cb1cb1cf1dd184318f97"
            },
            {
              "fixed": "a6940b84c8c035da465b7165fdfcfb005545724e"
            },
            {
              "fixed": "32134cf9211b83bed9076d0739c5906fbea4c763"
            },
            {
              "fixed": "5c7fc39bf19abb38a996aaad77b3e3a8f48581c3"
            },
            {
              "fixed": "89b1b79c308818a715e75f28744b70d8940a07c9"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.18.0"
            },
            {
              "fixed": "5.10.265"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.216"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.183"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.151"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.103"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.44"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80718.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk()\n\nIn pcpu_create_chunk(), nr_pages is the total contiguous backing\nallocation, i.e., nr_units * pcpu_unit_pages, but pcpu_chunk_populated()\nuses it to set chunk-\u003epopulated, whose size is pcpu_unit_pages, bitmap. \nSince bit N in chunk-\u003epopulated means page offset N inside every unit is\nbacked.  When nr_units \u003e 1, the function writes beyond chunk-\u003epopulated. \nFix it by using chunk-\u003enr_pages.\n\nIt also fixes the global pcpu_nr_empty_pop_pages accounting, since\npcpu_balance_free() only iterates up to chunk-\u003enr_pages.\n\nCommit a63d4ac4ab609 (\"percpu: make percpu-km set chunk-\u003epopulated bitmap\nproperly\") introduced the bitmap overflow issue.  Later, commit\nb539b87fed37f (\"percpu: implmeent pcpu_nr_empty_pop_pages and\nchunk-\u003enr_populated\") added pcpu_nr_empty_pop_pages and caused the\naccounting issue.",
  "id": "CVE-2026-80718",
  "modified": "2026-08-30T03:30:39.801315892Z",
  "published": "2026-08-28T06:53:15.490Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/01504da375f5b19df195cb1cb1cf1dd184318f97"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/32134cf9211b83bed9076d0739c5906fbea4c763"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5c7fc39bf19abb38a996aaad77b3e3a8f48581c3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5f43d2c1bea280dcdfabaf156c25e7402fb8039f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6fc7da2a052f2825fff785e860e67183f5acaaba"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/89b1b79c308818a715e75f28744b70d8940a07c9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/92c43ac3c2b09eb16162e8144e73c00b7c3e29d6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a6940b84c8c035da465b7165fdfcfb005545724e"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80718.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80718"
    },
    {
      "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": "mm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk()"
}