{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "198f0f4c58b9f481e4e51c8c70a6ab9852bbab7f"
            },
            {
              "fixed": "58321b4e6e4f0f412069ab27ccdd56292757343a"
            },
            {
              "fixed": "74fef68d521150281e36cdaa20e9e1ee3e3aa146"
            },
            {
              "fixed": "ef2ae10a4582bc92b7e944181bbd2f87f3d30f3a"
            },
            {
              "fixed": "9c8f31eaae6140ecadec0c07320498a944556de2"
            },
            {
              "fixed": "76e415ea88d20f022ed5cfcf78c50e156a267e91"
            },
            {
              "fixed": "35d4a3cf70a855b50e53189ac2f8463e20a02046"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.178"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.145"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.96"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.39"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64458.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/damon/ops-common: handle extreme intervals in damon_hot_score()\n\nFix three issues in damon_hot_score() that comes from wrong handling of\nextreme (zero or too high) monitoring intervals user setup.\n\nWhen the user sets sampling interval zero, damon_max_nr_accesses(), which\nis called from damon_hot_score(), causes a divide-by-zero.  Needless to\nsay, it is a problem.\n\nWhen the user sets the aggregation interval zero, the function returns\nzero.  It is wrong, since the real maximum nr_acceses in the setup should\nbe one.  Worse yet, it can cause another divide-by-zero from its caller,\ndamon_hot_score(), since it uses damon_max_nr_accesses() return value as a\ndenominator.\n\nWhen the user sets the aggregation interval very high, damon_hot_score()\ncould return a value out of [0, DAMOS_MAX_SCORE] range.  Since the return\nvalue is used as an index to the regions_score_histogram array, which is\nDAMOS_MAX_SCORE+1 size, it causes out of bounds array access.\n\nThe issues can be relatively easily reproduced like below.  The sysfs\nwrite permission is required, though.\n\n    # ./damo start --damos_action lru_prio --damos_quota_space 100M \\\n            --damos_quota_interval 1s\n    # cd /sys/kernel/mm/damon/admin/kdamonds/0\n    # echo 0 \u003e contexts/0/monitoring_attrs/intervals/sample_us\n    # echo 0 \u003e contexts/0/monitoring_attrs/intervals/aggr_us\n    # echo commit \u003e state\n    # dmesg\n    [...]\n    [  131.329762] Oops: divide error: 0000 [#1] SMP NOPTI\n    [...]\n    [  131.336089] RIP: 0010:damon_hot_score+0x27/0xd0\n    [...]\n\nFix the divide-by-zero intervals problems by explicitly handling the zero\nintervals in damon_max_nr_accesses().  Fix the out-of-bound array access\nby applying [0, DAMOS_MAX_SCORE] bounds before returning from\ndamon_hot_score().\n\nThe issue was discovered [1] by Sashiko.",
  "id": "CVE-2026-64458",
  "modified": "2026-07-27T03:56:39.543036913Z",
  "published": "2026-07-25T08:51:26.072Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/35d4a3cf70a855b50e53189ac2f8463e20a02046"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/58321b4e6e4f0f412069ab27ccdd56292757343a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/74fef68d521150281e36cdaa20e9e1ee3e3aa146"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/76e415ea88d20f022ed5cfcf78c50e156a267e91"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9c8f31eaae6140ecadec0c07320498a944556de2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ef2ae10a4582bc92b7e944181bbd2f87f3d30f3a"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64458.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64458"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "mm/damon/ops-common: handle extreme intervals in damon_hot_score()"
}