GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-74349 (GCVE-0-2026-74349)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:58 – Updated: 2026-08-17 05:46
VLAI
Title
ocfs2: reject FITRIM ranges shorter than a cluster
Summary
In the Linux kernel, the following vulnerability has been resolved: ocfs2: reject FITRIM ranges shorter than a cluster ocfs2_trim_mainbm() trims the global bitmap in cluster units, but its too-short range validation only checks sb->s_blocksize. On filesystems with a cluster size larger than the block size, a FITRIM range that is at least one block but shorter than one cluster is accepted and shifted down to len == 0. The later start + len - 1 and len -= ... arithmetic then underflows and can drive trimming past the requested range. Reject ranges shorter than s_clustersize instead. That preserves the existing -EINVAL behavior for requests that cannot discard even one allocation unit and keeps zero-cluster trims out of the group walk.
Severity
7.1 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: aa89762c54800208d5afdcd8e6bf124818f17fe0 , < d903d59c0315f59bdf0214b4f13d71c9feb2c45c (git)
Affected: aa89762c54800208d5afdcd8e6bf124818f17fe0 , < 441abb77222f155e8d931dbabb465466db01cfd7 (git)
Affected: aa89762c54800208d5afdcd8e6bf124818f17fe0 , < e652d0f5108e447b22da4249bcd23dd1b63c73dd (git)
Affected: aa89762c54800208d5afdcd8e6bf124818f17fe0 , < 346314bb0cc2fc52b50b73d6ecc62e0217455c2e (git)
Affected: aa89762c54800208d5afdcd8e6bf124818f17fe0 , < 06c0a0431b9856506fcd9b2c1b0c6136567d756d (git)
Affected: aa89762c54800208d5afdcd8e6bf124818f17fe0 , < 3fa7139b5f42731a61f78c42433adae13f9adc21 (git)
Affected: aa89762c54800208d5afdcd8e6bf124818f17fe0 , < 2c13e02592b918be7725ab5965e01ef4e46c4b57 (git)
Affected: aa89762c54800208d5afdcd8e6bf124818f17fe0 , < ca1afd88f5eaaff9168e1466e5401385edf59543 (git)
guessed Create a notification for this product.
Linux Linux Affected: 3.14
Unaffected: 0 , < 3.14 (semver)
Unaffected: 5.10.261 , ≤ 5.10.* (semver)
Unaffected: 5.15.212 , ≤ 5.15.* (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.97 , ≤ 6.12.* (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/ocfs2/alloc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "d903d59c0315f59bdf0214b4f13d71c9feb2c45c",
              "status": "affected",
              "version": "aa89762c54800208d5afdcd8e6bf124818f17fe0",
              "versionType": "git"
            },
            {
              "lessThan": "441abb77222f155e8d931dbabb465466db01cfd7",
              "status": "affected",
              "version": "aa89762c54800208d5afdcd8e6bf124818f17fe0",
              "versionType": "git"
            },
            {
              "lessThan": "e652d0f5108e447b22da4249bcd23dd1b63c73dd",
              "status": "affected",
              "version": "aa89762c54800208d5afdcd8e6bf124818f17fe0",
              "versionType": "git"
            },
            {
              "lessThan": "346314bb0cc2fc52b50b73d6ecc62e0217455c2e",
              "status": "affected",
              "version": "aa89762c54800208d5afdcd8e6bf124818f17fe0",
              "versionType": "git"
            },
            {
              "lessThan": "06c0a0431b9856506fcd9b2c1b0c6136567d756d",
              "status": "affected",
              "version": "aa89762c54800208d5afdcd8e6bf124818f17fe0",
              "versionType": "git"
            },
            {
              "lessThan": "3fa7139b5f42731a61f78c42433adae13f9adc21",
              "status": "affected",
              "version": "aa89762c54800208d5afdcd8e6bf124818f17fe0",
              "versionType": "git"
            },
            {
              "lessThan": "2c13e02592b918be7725ab5965e01ef4e46c4b57",
              "status": "affected",
              "version": "aa89762c54800208d5afdcd8e6bf124818f17fe0",
              "versionType": "git"
            },
            {
              "lessThan": "ca1afd88f5eaaff9168e1466e5401385edf59543",
              "status": "affected",
              "version": "aa89762c54800208d5afdcd8e6bf124818f17fe0",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/ocfs2/alloc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.14"
            },
            {
              "lessThan": "3.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.261",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.212",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.261",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.212",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.178",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "3.14",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: reject FITRIM ranges shorter than a cluster\n\nocfs2_trim_mainbm() trims the global bitmap in cluster units, but its\ntoo-short range validation only checks sb-\u003es_blocksize.\n\nOn filesystems with a cluster size larger than the block size, a FITRIM\nrange that is at least one block but shorter than one cluster is accepted\nand shifted down to len == 0.  The later start + len - 1 and len -= ... \narithmetic then underflows and can drive trimming past the requested\nrange.\n\nReject ranges shorter than s_clustersize instead.  That preserves the\nexisting -EINVAL behavior for requests that cannot discard even one\nallocation unit and keeps zero-cluster trims out of the group walk."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - Exploitation requires a local FITRIM ioctl on an open OCFS2 mount (typically via fstrim or ioctl on the mountpoint); there is no network-facing OCFS2 handler or remote protocol path to this code.\nAC:L - An attacker with the required privileges can reliably trigger the bug by supplying a FITRIM range at least one block long but shorter than one cluster, which is common when OCFS2 cluster size exceeds the 4K block size.\nPR:L - The FITRIM handler explicitly requires capable(CAP_SYS_ADMIN) before calling ocfs2_trim_fs(); per kernel CNA guidance this maps to Low because CAP_SYS_ADMIN can be held by root inside a user namespace.\nUI:N - No victim interaction is required; the privileged attacker directly issues the FITRIM ioctl with crafted range parameters to trigger the faulty trim logic.\nS:U - Impact is confined to erroneous discard/trim operations within the same privileged filesystem context on the affected host and shared storage; it does not cross VM, container, or IOMMU security boundaries.\nC:N - The flaw causes incorrect discard of free clusters via sb_issue_discard and integer underflow in range arithmetic; it does not read kernel memory, leak pointers, or expose sensitive data to the attacker.\nI:H - Unsigned underflow can drive trimming far beyond the requested FITRIM range, issuing discard on extensive free-space regions on shared cluster storage and risking unintended loss or corruption of filesystem data integrity.\nA:H - Corrupted len/last_group values can cause prolonged iteration through cluster groups while holding the exclusive OCFS2 cluster-wide trim DLM lock, enabling severe denial of service or hang for the node and other cluster members."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:46:12.774Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/d903d59c0315f59bdf0214b4f13d71c9feb2c45c"
        },
        {
          "url": "https://git.kernel.org/stable/c/441abb77222f155e8d931dbabb465466db01cfd7"
        },
        {
          "url": "https://git.kernel.org/stable/c/e652d0f5108e447b22da4249bcd23dd1b63c73dd"
        },
        {
          "url": "https://git.kernel.org/stable/c/346314bb0cc2fc52b50b73d6ecc62e0217455c2e"
        },
        {
          "url": "https://git.kernel.org/stable/c/06c0a0431b9856506fcd9b2c1b0c6136567d756d"
        },
        {
          "url": "https://git.kernel.org/stable/c/3fa7139b5f42731a61f78c42433adae13f9adc21"
        },
        {
          "url": "https://git.kernel.org/stable/c/2c13e02592b918be7725ab5965e01ef4e46c4b57"
        },
        {
          "url": "https://git.kernel.org/stable/c/ca1afd88f5eaaff9168e1466e5401385edf59543"
        }
      ],
      "title": "ocfs2: reject FITRIM ranges shorter than a cluster",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74349",
    "datePublished": "2026-08-15T05:58:36.630Z",
    "dateReserved": "2026-08-15T05:44:03.886Z",
    "dateUpdated": "2026-08-17T05:46:12.774Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74349",
      "date": "2026-09-04",
      "epss": "0.00126",
      "percentile": "0.02576"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74349\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-15T06:22:36.130\",\"lastModified\":\"2026-08-17T06:19:29.533\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nocfs2: reject FITRIM ranges shorter than a cluster\\n\\nocfs2_trim_mainbm() trims the global bitmap in cluster units, but its\\ntoo-short range validation only checks sb-\u003es_blocksize.\\n\\nOn filesystems with a cluster size larger than the block size, a FITRIM\\nrange that is at least one block but shorter than one cluster is accepted\\nand shifted down to len == 0.  The later start + len - 1 and len -= ... \\narithmetic then underflows and can drive trimming past the requested\\nrange.\\n\\nReject ranges shorter than s_clustersize instead.  That preserves the\\nexisting -EINVAL behavior for requests that cannot discard even one\\nallocation unit and keeps zero-cluster trims out of the group walk.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/ocfs2/alloc.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"aa89762c54800208d5afdcd8e6bf124818f17fe0\",\"lessThan\":\"d903d59c0315f59bdf0214b4f13d71c9feb2c45c\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"aa89762c54800208d5afdcd8e6bf124818f17fe0\",\"lessThan\":\"441abb77222f155e8d931dbabb465466db01cfd7\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"aa89762c54800208d5afdcd8e6bf124818f17fe0\",\"lessThan\":\"e652d0f5108e447b22da4249bcd23dd1b63c73dd\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"aa89762c54800208d5afdcd8e6bf124818f17fe0\",\"lessThan\":\"346314bb0cc2fc52b50b73d6ecc62e0217455c2e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"aa89762c54800208d5afdcd8e6bf124818f17fe0\",\"lessThan\":\"06c0a0431b9856506fcd9b2c1b0c6136567d756d\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"aa89762c54800208d5afdcd8e6bf124818f17fe0\",\"lessThan\":\"3fa7139b5f42731a61f78c42433adae13f9adc21\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"aa89762c54800208d5afdcd8e6bf124818f17fe0\",\"lessThan\":\"2c13e02592b918be7725ab5965e01ef4e46c4b57\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"aa89762c54800208d5afdcd8e6bf124818f17fe0\",\"lessThan\":\"ca1afd88f5eaaff9168e1466e5401385edf59543\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/ocfs2/alloc.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"3.14\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"3.14\",\"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:N/I:H/A:H\",\"baseScore\":7.1,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.2}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/06c0a0431b9856506fcd9b2c1b0c6136567d756d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/2c13e02592b918be7725ab5965e01ef4e46c4b57\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/346314bb0cc2fc52b50b73d6ecc62e0217455c2e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3fa7139b5f42731a61f78c42433adae13f9adc21\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/441abb77222f155e8d931dbabb465466db01cfd7\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ca1afd88f5eaaff9168e1466e5401385edf59543\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/d903d59c0315f59bdf0214b4f13d71c9feb2c45c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/e652d0f5108e447b22da4249bcd23dd1b63c73dd\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-20T20:53:03+00:00",
      "cve": "CVE-2026-74349",
      "id": "CVE-2026-74349",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: ocfs2: reject FITRIM ranges shorter than a cluster",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74349.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.