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CVE-2026-89574

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: dm array: validate array block headers on read array_block_check() validates blocknr and csum and nothing else, while node_check(), next to it, has bounded the structural fields since both were written. dm_array_cursor_next() takes its loop bound from the on-disk nr_entries and element_at() is unguarded pointer arithmetic, so a count larger than the block holds keeps the cursor in one block while the index grows past it and the read walks off the dm-bufio buffer -- dm_cache_load_mappings() drives it once per cache block at activation. Check the header against itself: reject a zero value_size, require max_entries to equal calc_max_entries() for that value_size and block size, and require nr_entries to fit. Equality rather than an upper bound, since a count below the real capacity trips BUG_ON() in fill_ablock() and trim_ablock(). Metadata dm-array writes satisfies all three.

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-11 20:19:41.517000
Last modified
2026-10-30 13:20:22.063000
View original CVE JSON 
{
  "id": "CVE-2026-89574",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-11T20:19:41.517",
  "lastModified": "2026-10-30T13:20:22.063",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndm array: validate array block headers on read\n\narray_block_check() validates blocknr and csum and nothing else, while\nnode_check(), next to it, has bounded the structural fields since both\nwere written. dm_array_cursor_next() takes its loop bound from the\non-disk nr_entries and element_at() is unguarded pointer arithmetic, so\na count larger than the block holds keeps the cursor in one block while\nthe index grows past it and the read walks off the dm-bufio buffer --\ndm_cache_load_mappings() drives it once per cache block at activation.\n\nCheck the header against itself: reject a zero value_size, require\nmax_entries to equal calc_max_entries() for that value_size and block\nsize, and require nr_entries to fit. Equality rather than an upper bound,\nsince a count below the real capacity trips BUG_ON() in fill_ablock() and\ntrim_ablock(). Metadata dm-array writes satisfies all three."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/md/persistent-data/dm-array.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6513c29f44f2cc970c0e9fecfe5a6526c3e73025",
              "lessThan": "e09d8b34ed199c8b7d7528c2b8324aa7cff712f8",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6513c29f44f2cc970c0e9fecfe5a6526c3e73025",
              "lessThan": "0e3b8f371c385c212b6e6f76c66f5b3f5bcfea62",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6513c29f44f2cc970c0e9fecfe5a6526c3e73025",
              "lessThan": "67adda7ed5da3e3b64f5b9021a02c21fb374fd9c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6513c29f44f2cc970c0e9fecfe5a6526c3e73025",
              "lessThan": "b33f76d33aaeacf3baf3370d8d64985169b36600",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6513c29f44f2cc970c0e9fecfe5a6526c3e73025",
              "lessThan": "9808ddffb4bc659352df3020cd84d9d864820ee5",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6513c29f44f2cc970c0e9fecfe5a6526c3e73025",
              "lessThan": "2965787723084835b18dfe993cd450ebf5bd4540",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/md/persistent-data/dm-array.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3.9",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "3.9",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.109",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.50",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.4",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "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": "2026-10-16T19:24:26.489606Z",
          "id": "CVE-2026-89574",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0e3b8f371c385c212b6e6f76c66f5b3f5bcfea62",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2965787723084835b18dfe993cd450ebf5bd4540",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/67adda7ed5da3e3b64f5b9021a02c21fb374fd9c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9808ddffb4bc659352df3020cd84d9d864820ee5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b33f76d33aaeacf3baf3370d8d64985169b36600",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e09d8b34ed199c8b7d7528c2b8324aa7cff712f8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}