CVE-2024-26704

Status: ModifiedHigh (7.8)—
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix double-free of blocks due to wrong extents moved_len
In ext4_move_extents(), moved_len is only updated when all moves are successfully executed, and only discards orig_inode and donor_inode preallocations when moved_len is not zero. When the loop fails to exit after successfully moving some extents, moved_len is not updated and remains at 0, so it does not discard the preallocations.
If the moved extents overlap with the preallocated extents, the overlapped extents are freed twice in ext4_mb_release_inode_pa() and ext4_process_freed_data() (as described in commit 94d7c16cbbbd ("ext4: Fix double-free of blocks with EXT4_IOC_MOVE_EXT")), and bb_free is incremented twice.
Read full descriptionShow less
Hence when trim is executed, a zero-division bug is triggered in mb_update_avg_fragment_size() because bb_free is not zero and bb_fragments is zero.
Therefore, update move_len after each extent move to avoid the issue.
CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 7.8
Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.27%
Percentile among all scored CVEs: 17
Score date: 10/8/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (2)

Debian — Debian Linux Linux — Linux Kernel
CWEs

CWE-415
References

Raw JSON (NVD)

Show
{
  "id": "CVE-2024-26704",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2024-26704",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2024-09-10T15:52:39.832740Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.8,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 1.8
      },
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.8,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a",
              "lessThan": "b4fbb89d722cbb16beaaea234b7230faaaf68c71",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a",
              "lessThan": "afbcad9ae7d6d11608399188f03a837451b6b3a1",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a",
              "lessThan": "d033a555d9a1cf53dbf3301af7199cc4a4c8f537",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a",
              "lessThan": "afba9d11320dad5ce222ac8964caf64b7b4bedb1",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a",
              "lessThan": "185eab30486ba3e7bf8b9c2e049c79a06ffd2bc1",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a",
              "lessThan": "2883940b19c38d5884c8626483811acf4d7e148f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a",
              "lessThan": "559ddacb90da1d8786dd8ec4fd76bbfa404eaef6",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a",
              "lessThan": "55583e899a5357308274601364741a83e78d6ac4",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/ext4/move_extent.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.18"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "3.18",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "4.19.307",
              "versionType": "semver",
              "lessThanOrEqual": "4.19.*"
            },
            {
              "status": "unaffected",
              "version": "5.4.269",
              "versionType": "semver",
              "lessThanOrEqual": "5.4.*"
            },
            {
              "status": "unaffected",
              "version": "5.10.210",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.149",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.79",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.18",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.7.6",
              "versionType": "semver",
              "lessThanOrEqual": "6.7.*"
            },
            {
              "status": "unaffected",
              "version": "6.8",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/ext4/move_extent.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2024-04-03T15:15:53.193",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/185eab30486ba3e7bf8b9c2e049c79a06ffd2bc1",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2883940b19c38d5884c8626483811acf4d7e148f",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/55583e899a5357308274601364741a83e78d6ac4",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/559ddacb90da1d8786dd8ec4fd76bbfa404eaef6",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/afba9d11320dad5ce222ac8964caf64b7b4bedb1",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/afbcad9ae7d6d11608399188f03a837451b6b3a1",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b4fbb89d722cbb16beaaea234b7230faaaf68c71",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d033a555d9a1cf53dbf3301af7199cc4a4c8f537",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/185eab30486ba3e7bf8b9c2e049c79a06ffd2bc1",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/2883940b19c38d5884c8626483811acf4d7e148f",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/55583e899a5357308274601364741a83e78d6ac4",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/559ddacb90da1d8786dd8ec4fd76bbfa404eaef6",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/afba9d11320dad5ce222ac8964caf64b7b4bedb1",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/afbcad9ae7d6d11608399188f03a837451b6b3a1",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/b4fbb89d722cbb16beaaea234b7230faaaf68c71",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/d033a555d9a1cf53dbf3301af7199cc4a4c8f537",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html",
      "tags": [
        "Mailing List"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html",
      "tags": [
        "Mailing List"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-415"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix double-free of blocks due to wrong extents moved_len\n\nIn ext4_move_extents(), moved_len is only updated when all moves are\nsuccessfully executed, and only discards orig_inode and donor_inode\npreallocations when moved_len is not zero. When the loop fails to exit\nafter successfully moving some extents, moved_len is not updated and\nremains at 0, so it does not discard the preallocations.\n\nIf the moved extents overlap with the preallocated extents, the\noverlapped extents are freed twice in ext4_mb_release_inode_pa() and\next4_process_freed_data() (as described in commit 94d7c16cbbbd (\"ext4:\nFix double-free of blocks with EXT4_IOC_MOVE_EXT\")), and bb_free is\nincremented twice. Hence when trim is executed, a zero-division bug is\ntriggered in mb_update_avg_fragment_size() because bb_free is not zero\nand bb_fragments is zero.\n\nTherefore, update move_len after each extent move to avoid the issue."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: corrige la doble liberación de bloques debido a extensiones incorrectas. moving_len En ext4_move_extents(), move_len solo se actualiza cuando todos los movimientos se ejecutan exitosamente y solo descarta las preasignaciones de orig_inode y donante_inode cuando se mueve_len no es cero. Cuando el bucle no sale después de mover con éxito algunas extensiones, moving_len no se actualiza y permanece en 0, por lo que no descarta las asignaciones previas. Si las extensiones movidas se superponen con las extensiones preasignadas, las extensiones superpuestas se liberan dos veces en ext4_mb_release_inode_pa() y ext4_process_freed_data() (como se describe en el commit 94d7c16cbbbd (\"ext4: corrige la doble liberación de bloques con EXT4_IOC_MOVE_EXT\")), y se incrementa bb_free dos veces. Por lo tanto, cuando se ejecuta trim, se activa un error de división cero en mb_update_avg_fragment_size() porque bb_free no es cero y bb_fragments es cero. Por lo tanto, actualice move_len después de cada movimiento de extensión para evitar el problema."
    }
  ],
  "lastModified": "2026-08-04T11:16:57.693",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "EC92BBA6-F902-49DB-8E8D-3381C8E499EF",
              "versionEndExcluding": "4.19.307",
              "versionStartIncluding": "3.18"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "319545F3-D56C-4751-BEBF-0505478BBAE8",
              "versionEndExcluding": "5.4.269",
              "versionStartIncluding": "4.20"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F5CB4CA6-A9A0-4AFD-9102-8CF94D708170",
              "versionEndExcluding": "5.10.210",
              "versionStartIncluding": "5.5"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "0D0465BB-4053-4E15-9137-6696EBAE90FD",
              "versionEndExcluding": "5.15.149",
              "versionStartIncluding": "5.11"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "656E2F29-1779-4EFC-AA64-8F984E2885B1",
              "versionEndExcluding": "6.1.79",
              "versionStartIncluding": "5.16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "BD961E49-FEDA-47CF-BF23-4D2BD942B4E0",
              "versionEndExcluding": "6.6.18",
              "versionStartIncluding": "6.2"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "C6D6A5C8-7308-42A9-8A72-ABF3DEA4BB82",
              "versionEndExcluding": "6.7.6",
              "versionStartIncluding": "6.7"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B9F4EA73-0894-400F-A490-3A397AB7A517"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "056BD938-0A27-4569-B391-30578B309EE3"
            }
          ],
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "07B237A9-69A3-4A9C-9DA0-4E06BD37AE73"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}