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CVE-2026-72105

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: dm-log: fix a bitset_size overflow on 32bit machines Commit c20e36b7631d ("dm log: fix out-of-bounds write due to region_count overflow") made sure that region_count could fit in an unsigned int. But the bitmap memory isn't allocated based on region_count. It uses bitset_size (a size_t variable). The first step of calculating bitset_size is to set it to region_count, rounded up to a multiple of BITS_PER_LONG. If region_size is less than BITS_PER_LONG smaller than UINT_MAX, it will get rounded up to 2^32. On a 32bit architecture, this will make bitset_size wrap around to 0 and fail, despite region_count being valid. Since bitset_size gets divided by 8, it can hold any valid region_count. It just needs a special case to handle the rollover. If it is 0, the value rolled over, and bitset size should be set to the number of bytes needed to hold 2^32 bits.

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-15 06:21:24.673000
Last modified
2026-10-19 22:17:27.703000
View original CVE JSON 
{
  "id": "CVE-2026-72105",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-15T06:21:24.673",
  "lastModified": "2026-10-19T22:17:27.703",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm-log: fix a bitset_size overflow on 32bit machines\n\nCommit c20e36b7631d (\"dm log: fix out-of-bounds write due to\nregion_count overflow\") made sure that region_count could fit in an\nunsigned int. But the bitmap memory isn't allocated based on\nregion_count. It uses bitset_size (a size_t variable). The first step of\ncalculating bitset_size is to set it to region_count, rounded up to a\nmultiple of BITS_PER_LONG. If region_size is less than BITS_PER_LONG\nsmaller than UINT_MAX, it will get rounded up to 2^32. On a 32bit\narchitecture, this will make bitset_size wrap around to 0 and fail,\ndespite region_count being valid.\n\nSince bitset_size gets divided by 8, it can hold any valid region_count.\nIt just needs a special case to handle the rollover. If it is 0, the\nvalue rolled over, and bitset size should be set to the number of bytes\nneeded to hold 2^32 bits."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/md/dm-log.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "44ab8875ae4a2842bde2d756bed195d375e0debb",
              "lessThan": "cdc4ddf9db2cb79f4ab86b1a509b7ac21b0b6cf5",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "defe483e47173768c227532694dc78cb65db5f09",
              "lessThan": "4b0de5a3ac1fd42acb0dc1f80ac5747e3287d723",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "3ec74da927b4e171a6fc0e77b1188ba4d019af51",
              "lessThan": "567602fa72d57169365cbc589e0b8c3be900636d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d4ac87567f86a55c3c92e9a5144dcd943a9772a1",
              "lessThan": "d05e0edfecf5260e6dddd28b2f0cce02bfc6ed7a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "12bd5b88e91a02785244ff1d20fb157e96e9cdc8",
              "lessThan": "1c3412b584e1fb6c665ff33ba7259253bc0082cb",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "b455903eed4558982be0811f5b7f44f6bbc4ff57",
              "lessThan": "e0b0163a65758ec3a2361ae1cea407898c27f21e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c20e36b7631d83e7535877f08af8b0af72c44b1a",
              "lessThan": "79feb87ab2396d49b9b65e4bb815d33cc71cba47",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "c20e36b7631d83e7535877f08af8b0af72c44b1a",
              "lessThan": "9743132a41f4d9d0e54c5f2adcb821b04796bab1",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4ec8323b9f0764a14d532b1ae9b87f8a9fecb867",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5.10.258",
              "lessThan": "5.10.261",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "5.15.209",
              "lessThan": "5.15.212",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.1.175",
              "lessThan": "6.1.178",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.6.141",
              "lessThan": "6.6.145",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.12.91",
              "lessThan": "6.12.97",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.18.33",
              "lessThan": "6.18.40",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "7.0.10",
              "lessThan": "7.1",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/md/dm-log.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7.1",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "7.1",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.261",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.212",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.178",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.145",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.97",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.40",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.5",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T15:52:08.599167Z",
          "id": "CVE-2026-72105",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-190"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1c3412b584e1fb6c665ff33ba7259253bc0082cb",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4b0de5a3ac1fd42acb0dc1f80ac5747e3287d723",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/567602fa72d57169365cbc589e0b8c3be900636d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/79feb87ab2396d49b9b65e4bb815d33cc71cba47",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9743132a41f4d9d0e54c5f2adcb821b04796bab1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cdc4ddf9db2cb79f4ab86b1a509b7ac21b0b6cf5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d05e0edfecf5260e6dddd28b2f0cce02bfc6ed7a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e0b0163a65758ec3a2361ae1cea407898c27f21e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}