CVE-2026-98124 (GCVE-0-2026-98124)

Vulnerability from cvelistv5 – Published: 2026-09-25 10:36 – Updated: 2026-10-21 12:54
VLAI
Title
smb/client: invalidate fscache for fallocate range operations
Summary
In the Linux kernel, the following vulnerability has been resolved: smb/client: invalidate fscache for fallocate range operations smb3_zero_range(), smb3_punch_hole(), smb3_insert_range(), and smb3_collapse_range() modify file contents through server-side range operations. These operations discard the affected page cache, but leave the FS-Cache cookie valid, so a later read may return data cached before the range operation. Fix this by invalidating FS-Cache after outstanding I/O has completed and before modifying the file on the server. Run the following as root on a CIFS mount with fsc enabled and an active CacheFiles backend: bash -c ' MNT=/mnt/cifs FILE="$MNT/repro" # Generate four 1 MiB random blocks: [A][B][C][D]. dd if=/dev/urandom of=/tmp/src bs=1M count=4 status=none # Expected contents after zeroing B: [A][zero][C][D]. cp /tmp/src /tmp/expected dd if=/dev/zero of=/tmp/expected bs=1M seek=1 count=1 \ conv=notrunc status=none cp /tmp/src "$FILE" # Populate FS-Cache, then discard the page cache. sync echo 1 > /proc/sys/vm/drop_caches cat "$FILE" > /dev/null sync echo 1 > /proc/sys/vm/drop_caches fallocate --zero-range -o 1M -l 1M "$FILE" if cmp -s /tmp/expected "$FILE"; then echo "readback: OK" else echo "readback: STALE DATA" fi ' Before this change, the readback differs from /tmp/expected: readback: STALE DATA After this change, it matches: readback: OK
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7061 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 31742c5a331766bc7df6b0d525df00c6cd20d5a6 , < cc7202a51b8777a757bda9dcfbf339f828c6a130 (git)
Affected: 31742c5a331766bc7df6b0d525df00c6cd20d5a6 , < dd8b1e808f5c19479e6ed47e2f88a1fd46f8b0e5 (git)
Affected: 31742c5a331766bc7df6b0d525df00c6cd20d5a6 , < 93c6e5a8d7c5071d586c1411596d5db5faad22b2 (git)
Affected: 31742c5a331766bc7df6b0d525df00c6cd20d5a6 , < 448ba0ae65ca61064183564d2983c9aa59bd6ba7 (git)
guessed Create a notification for this product.
Linux Linux Affected: 3.17
Unaffected: 0 , < 3.17 (semver)
Unaffected: 6.6.160 , ≤ 6.6.* (semver)
Unaffected: 6.12.114 , ≤ 6.12.* (semver)
Unaffected: 7.2.7 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (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/smb/client/smb2ops.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "cc7202a51b8777a757bda9dcfbf339f828c6a130",
              "status": "affected",
              "version": "31742c5a331766bc7df6b0d525df00c6cd20d5a6",
              "versionType": "git"
            },
            {
              "lessThan": "dd8b1e808f5c19479e6ed47e2f88a1fd46f8b0e5",
              "status": "affected",
              "version": "31742c5a331766bc7df6b0d525df00c6cd20d5a6",
              "versionType": "git"
            },
            {
              "lessThan": "93c6e5a8d7c5071d586c1411596d5db5faad22b2",
              "status": "affected",
              "version": "31742c5a331766bc7df6b0d525df00c6cd20d5a6",
              "versionType": "git"
            },
            {
              "lessThan": "448ba0ae65ca61064183564d2983c9aa59bd6ba7",
              "status": "affected",
              "version": "31742c5a331766bc7df6b0d525df00c6cd20d5a6",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2ops.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.17"
            },
            {
              "lessThan": "3.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.114",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.7",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.160",
                  "versionStartIncluding": "3.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.114",
                  "versionStartIncluding": "3.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.7",
                  "versionStartIncluding": "3.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "3.17",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: invalidate fscache for fallocate range operations\n\nsmb3_zero_range(), smb3_punch_hole(), smb3_insert_range(), and\nsmb3_collapse_range() modify file contents through server-side range\noperations. These operations discard the affected page cache, but leave\nthe FS-Cache cookie valid, so a later read may return data cached before\nthe range operation.\n\nFix this by invalidating FS-Cache after outstanding I/O has completed\nand before modifying the file on the server.\n\nRun the following as root on a CIFS mount with fsc enabled and an active\nCacheFiles backend:\n\n        bash -c \u0027\n                MNT=/mnt/cifs\n                FILE=\"$MNT/repro\"\n\n                # Generate four 1 MiB random blocks: [A][B][C][D].\n                dd if=/dev/urandom of=/tmp/src bs=1M count=4 status=none\n\n                # Expected contents after zeroing B: [A][zero][C][D].\n                cp /tmp/src /tmp/expected\n                dd if=/dev/zero of=/tmp/expected bs=1M seek=1 count=1 \\\n                        conv=notrunc status=none\n                cp /tmp/src \"$FILE\"\n\n                # Populate FS-Cache, then discard the page cache.\n                sync\n                echo 1 \u003e /proc/sys/vm/drop_caches\n                cat \"$FILE\" \u003e /dev/null\n                sync\n                echo 1 \u003e /proc/sys/vm/drop_caches\n\n                fallocate --zero-range -o 1M -l 1M \"$FILE\"\n\n                if cmp -s /tmp/expected \"$FILE\"; then\n                        echo \"readback: OK\"\n                else\n                        echo \"readback: STALE DATA\"\n                fi\n        \u0027\n\nBefore this change, the readback differs from /tmp/expected:\n\n        readback: STALE DATA\n\nAfter this change, it matches:\n\n        readback: OK"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-21T12:54:35.267Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/cc7202a51b8777a757bda9dcfbf339f828c6a130"
        },
        {
          "url": "https://git.kernel.org/stable/c/dd8b1e808f5c19479e6ed47e2f88a1fd46f8b0e5"
        },
        {
          "url": "https://git.kernel.org/stable/c/93c6e5a8d7c5071d586c1411596d5db5faad22b2"
        },
        {
          "url": "https://git.kernel.org/stable/c/448ba0ae65ca61064183564d2983c9aa59bd6ba7"
        }
      ],
      "title": "smb/client: invalidate fscache for fallocate range operations",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-98124",
    "datePublished": "2026-09-25T10:36:06.581Z",
    "dateReserved": "2026-09-25T10:25:14.318Z",
    "dateUpdated": "2026-10-21T12:54:35.267Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-98124",
      "date": "2026-10-23",
      "epss": "0.00186",
      "percentile": "0.07776"
    },
    "microsoft_vex": {
      "current_release_date": "2026-10-23T01:07:16.000Z",
      "cve": "CVE-2026-98124",
      "id": "msrc_CVE-2026-98124",
      "initial_release_date": "2026-09-28T00:09:01.000Z",
      "product_status:known_affected": "1",
      "product_status:under_investigation": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "smb/client: invalidate fscache for fallocate range operations",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-98124.json",
      "version": "3"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "fs/smb/client/smb2ops.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "cc7202a51b8777a757bda9dcfbf339f828c6a130",
                    "status": "affected",
                    "version": "31742c5a331766bc7df6b0d525df00c6cd20d5a6",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "dd8b1e808f5c19479e6ed47e2f88a1fd46f8b0e5",
                    "status": "affected",
                    "version": "31742c5a331766bc7df6b0d525df00c6cd20d5a6",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "93c6e5a8d7c5071d586c1411596d5db5faad22b2",
                    "status": "affected",
                    "version": "31742c5a331766bc7df6b0d525df00c6cd20d5a6",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "448ba0ae65ca61064183564d2983c9aa59bd6ba7",
                    "status": "affected",
                    "version": "31742c5a331766bc7df6b0d525df00c6cd20d5a6",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "fs/smb/client/smb2ops.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "3.17"
                  },
                  {
                    "lessThan": "3.17",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.160",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.114",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.2.*",
                    "status": "unaffected",
                    "version": "7.2.7",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.3",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "438C480C-978E-4F8C-A37D-7CB29AE32E61",
                    "versionEndExcluding": "6.6.160",
                    "versionStartIncluding": "3.17.1",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:-:*:*:*:*:*:*",
                    "matchCriteriaId": "7DD957C0-0777-4304-9BCA-7E8429CBE3D3",
                    "versionEndExcluding": "6.12.114",
                    "versionStartIncluding": "6.7",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "BACEDE75-270F-419E-A22D-025914C6BA15",
                    "versionEndExcluding": "7.2.7",
                    "versionStartIncluding": "6.13",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:3.17:-:*:*:*:*:*:*",
                    "matchCriteriaId": "3A351B03-87A0-405B-8A9B-488E173E1E3B",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:3.17:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "434E8752-0D8B-42E1-8B8F-23C409AB442C",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:3.17:rc3:*:*:*:*:*:*",
                    "matchCriteriaId": "D64AD3CD-8D3C-4749-9042-969F524DCB68",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:3.17:rc4:*:*:*:*:*:*",
                    "matchCriteriaId": "4B4E29E3-9F10-43B1-A349-1F7484F6015A",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:3.17:rc5:*:*:*:*:*:*",
                    "matchCriteriaId": "4223286C-F679-4FEC-B144-1C3B942BD506",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:3.17:rc6:*:*:*:*:*:*",
                    "matchCriteriaId": "C889AAA8-186E-433F-A31D-FF09221E1EBC",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:3.17:rc7:*:*:*:*:*:*",
                    "matchCriteriaId": "80BC78EE-50D8-4561-A6A6-A370E72F215B",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.13:-:*:*:*:*:*:*",
                    "matchCriteriaId": "5A3F9505-6B98-4269-8B81-127E55A1BF00",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:7.3:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "11E35E1B-5DB4-4AB9-9706-CD73B799EADF",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: invalidate fscache for fallocate range operations\n\nsmb3_zero_range(), smb3_punch_hole(), smb3_insert_range(), and\nsmb3_collapse_range() modify file contents through server-side range\noperations. These operations discard the affected page cache, but leave\nthe FS-Cache cookie valid, so a later read may return data cached before\nthe range operation.\n\nFix this by invalidating FS-Cache after outstanding I/O has completed\nand before modifying the file on the server.\n\nRun the following as root on a CIFS mount with fsc enabled and an active\nCacheFiles backend:\n\n        bash -c \u0027\n                MNT=/mnt/cifs\n                FILE=\"$MNT/repro\"\n\n                # Generate four 1 MiB random blocks: [A][B][C][D].\n                dd if=/dev/urandom of=/tmp/src bs=1M count=4 status=none\n\n                # Expected contents after zeroing B: [A][zero][C][D].\n                cp /tmp/src /tmp/expected\n                dd if=/dev/zero of=/tmp/expected bs=1M seek=1 count=1 \\\n                        conv=notrunc status=none\n                cp /tmp/src \"$FILE\"\n\n                # Populate FS-Cache, then discard the page cache.\n                sync\n                echo 1 \u003e /proc/sys/vm/drop_caches\n                cat \"$FILE\" \u003e /dev/null\n                sync\n                echo 1 \u003e /proc/sys/vm/drop_caches\n\n                fallocate --zero-range -o 1M -l 1M \"$FILE\"\n\n                if cmp -s /tmp/expected \"$FILE\"; then\n                        echo \"readback: OK\"\n                else\n                        echo \"readback: STALE DATA\"\n                fi\n        \u0027\n\nBefore this change, the readback differs from /tmp/expected:\n\n        readback: STALE DATA\n\nAfter this change, it matches:\n\n        readback: OK"
          }
        ],
        "id": "CVE-2026-98124",
        "lastModified": "2026-10-22T16:38:53.723",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2026-09-25T11:17:43.720",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/448ba0ae65ca61064183564d2983c9aa59bd6ba7"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/93c6e5a8d7c5071d586c1411596d5db5faad22b2"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/cc7202a51b8777a757bda9dcfbf339f828c6a130"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/dd8b1e808f5c19479e6ed47e2f88a1fd46f8b0e5"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-672"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2026-10-22T21:18:17+00:00",
      "cve": "CVE-2026-98124",
      "id": "CVE-2026-98124",
      "initial_release_date": "2026-09-25T00:00:00+00:00",
      "product_status:known_affected": "236",
      "product_status:known_not_affected": "42",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: smb/client: invalidate fscache for fallocate range operations",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98124.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-10-20T00:04:13Z",
      "cve": "CVE-2026-98124",
      "id": "CVE-2026-98124",
      "initial_release_date": "2026-09-25T23:46:33Z",
      "product_status:known_affected": "344",
      "product_status:known_not_affected": "4",
      "product_status:recommended": "4",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-98124",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/2026/cve-2026-98124.json",
      "version": "6"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.