CVE-2026-99274

smb: client: fix fiemap wild read on empty truncated response

Products / packages Linux

Published 07/11/2026, 14:08:45 UTC

Severity and exploitation

Not in CISA KEVNo CVSS score

KEV coverage does not rule out exploitation.

KEV checked 14/11/2026, 21:30:34 UTC

Severity

unknown

CVSS measures technical severity, not the likelihood of an attack.

Known exploitation

Not listed in the checked CISA KEV catalog

Absence from CISA KEV does not rule out attacks.

Public exploit

Not established by this record

Missing evidence does not mean no public exploit exists.

Remediation

Fix status not established

No structured fix or guidance is available here. Check the latest publisher advisory.

What this means

In the Linux kernel, the following vulnerability has been resolved:

Source excerpt · Linux

Attack conditions

Also require the last range in a truncated blob to advance the resume offset without overflowing, and to stay within the requested range; a malicious or broken server could otherwise make no progress or underflow len and loop forever.

Excerpt from the original source description below.

Review supporting sources →

Affected versions

Check the exact model, release, and any platform requirements against your installation.

Linux · Linux

Linux

4 ranges

Linux version evidence

Check a product version

Compare with this publisher’s ranges. This does not inspect your installation.

affected

2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4 → before 8e0d425b808c367f5033eb72aa4528ae18473627

git versions

2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4 → before 4a426ca5be7e3dedbe76575b967db04fbf01136f

git versions

2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4 → before 31f6dbb29fe17fa9595c7e8b19fd92915b03a4ca

git versions

2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4 → before f5baa17a0f316c235d61623ac8e8fb32c2b3c0cc

git versions

Other versions: unaffected

Linux · Linux

Linux

6 ranges

Linux version evidence

Check a product version

Compare with this publisher’s ranges. This does not inspect your installation.

affected

5.2

unaffected

0 → before 5.2

semver versions

6.12.117 → through 6.12.*

semver versions

6.18.61 → through 6.18.*

semver versions

7.3.2 → through 7.3.*

semver versions

7.4-rc1 → through *

original_commit_for_fix versions

Other versions: affected

Automatic dependency matching is unavailable for this record. Use the product evidence and publisher’s instructions to check your installation.

What to do

Compare your installed product and version with the affected versions above. A matching product name alone does not confirm exposure.

No structured fix or remediation guidance is available here. Check the full source description and vendor’s latest advisory for a patch or workaround; do not assume another version is safe.

cve.new guidance unless attributed to a publisher. This page does not inspect your installation.

Public exploit evidence

No public exploit reference is identified in the imported evidence. This is not a claim that no exploit exists.

Original source description

Read the full publisher description

In the Linux kernel, the following vulnerability has been resolved:

smb: client: fix fiemap wild read on empty truncated response

smb3_fiemap() treats -E2BIG from SMB2_ioctl() as a truncated range blob and loops for the next chunk. If the server reports STATUS_BUFFER_OVERFLOW with OutputCount == 0, SMB2_ioctl() returns -E2BIG with out_data == NULL and out_data_len == 0, and the existing length checks accept the empty result. The loop then evaluates

next = out_data[num - 1].file_offset + ...

with num == 0, reading 16 bytes before NULL.

Reject a truncated range blob that contains no range, so the resume offset is never computed from an empty response. Also require the last range in a truncated blob to advance the resume offset without overflowing, and to stay within the requested range; a malicious or broken server could otherwise make no progress or underflow len and loop forever. Free the previous response buffer before retrying.

Reproduced on 6.6.87.2 with a malicious SMB2 server that answers FSCTL_QUERY_ALLOCATED_RANGES with STATUS_BUFFER_OVERFLOW and OutputCount == 0; an FS_IOC_FIEMAP ioctl on the mount oopses in cifs_fiemap() with CR2 = fffffffffffffff8. The code path is unchanged on mainline.

References

4 sources

git.kernel.org/stable/c/8e0d425b808c367f5033eb72aa4528ae18473627

Source referenceLinux

git.kernel.org/stable/c/4a426ca5be7e3dedbe76575b967db04fbf01136f

Source referenceLinux

git.kernel.org/stable/c/31f6dbb29fe17fa9595c7e8b19fd92915b03a4ca

Source referenceLinux

git.kernel.org/stable/c/f5baa17a0f316c235d61623ac8e8fb32c2b3c0cc

Source referenceLinux

Inside the record

Evidence available

Package identity · not supplied

Version evidence

Remediation guidance · not supplied

Weakness classification · not supplied

Additional publishers · not supplied

Describes the evidence in this view, not whether the product is safe.

Original records

CVE-2026-99274

View the latest unmodified CVE JSON from the official source. It may be newer than this imported page.

cve.new JSON →

Environment requirements

These conditions apply together as specified by the publisher. A matching product name alone does not establish exposure.

Linux · platform conditions

Any condition may hold

Vulnerable product

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

From (inclusive): 5.2

After:

Through (inclusive):

Before: 6.12.117

Vulnerable product

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

From (inclusive): 5.2

After:

Through (inclusive):

Before: 6.18.61

Vulnerable product

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

From (inclusive): 5.2

After:

Through (inclusive):

Before: 7.3.2

Vulnerable product

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

From (inclusive): 5.2

After:

Through (inclusive):

Before: 7.4-rc1

Applicability preview

[
  {
    "nodes": [
      {
        "operator": "OR",
        "negate": false,
        "cpeMatch": [
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionStartIncluding": "5.2",
            "versionEndExcluding": "6.12.117"
          },
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionStartIncluding": "5.2",
            "versionEndExcluding": "6.18.61"
          },
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionStartIncluding": "5.2",
            "versionEndExcluding": "7.3.2"
          },
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionStartIncluding": "5.2",
            "versionEndExcluding": "7.4-rc1"
          }
        ]
      }
    ]
  }
]

Contributing organizations · 1

Linux

Assigning organization

2026-11-10

Timeline

All times UTC

7 Nov 2026, 14:08
Advisory published
Publication date supplied by the source.
10 Nov 2026, 18:15
Source updated
Latest modification date supplied by the source.
10 Nov 2026, 18:25
Last imported by cve.new
Latest catalog import, not the date we first saw this advisory.

What changed

Follow changes

CVE · CVE-2026-992742026-11-10

Observed 2026-11-10T18:25:52.242Z · upstream updated 2026-11-10T18:15:27.974Z

Product or version evidence changed

before

[
  {
    "vendor": "Linux",
    "name": "Linux",
    "platforms": [],
    "versions": [
      {
        "version": "2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4",
        "status": "affected",
        "lessThan": "4a426ca5be7e3dedbe76575b967db04fbf01136f",
        "versionType": "git"
      },
      {
        "version": "2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4",
        "status": "affected",
        "lessThan": "31f6dbb29fe17fa9595c7e8b19fd92915b03a4ca",
        "versionType": "git"
      },
      {
        "version": "2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4",
        "status": "affected",
        "lessThan": "f5baa17a0f316c235d61623ac8e8fb32c2b3c0cc",
        "versionType": "git"
      }
    ],
    "defaultStatus": "unaffected",
    "cpes": [],
    "source": "Linux",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-99274"
  },
  {
    "vendor": "Linux",
    "name": "Linux",
    "platforms": [],
    "versions": [
      {
        "version": "5.2",
        "status": "affected"
      },
      {
        "version": "0",
        "status": "unaffected",
        "lessThan": "5.2",
        "versionType": "semver"
      },
      {
        "version": "6.18.61",
        "status": "unaffected",
        "lessThanOrEqual": "6.18.*",
        "versionType": "semver"
      },
      {
        "version": "7.3.2",
        "status": "unaffected",
        "lessThanOrEqual": "7.3.*",
        "versionType": "semver"
      },
      {
        "version": "7.4-rc1",
        "status": "unaffected",
        "lessThanOrEqual": "*",
        "versionType": "original_commit_for_fix"
      }
    ],
    "defaultStatus": "affected",
    "cpes": [],
    "source": "Linux",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-99274"
  }
]

after

[
  {
    "vendor": "Linux",
    "name": "Linux",
    "platforms": [],
    "versions": [
      {
        "version": "2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4",
        "status": "affected",
        "lessThan": "8e0d425b808c367f5033eb72aa4528ae18473627",
        "versionType": "git"
      },
      {
        "version": "2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4",
        "status": "affected",
        "lessThan": "4a426ca5be7e3dedbe76575b967db04fbf01136f",
        "versionType": "git"
      },
      {
        "version": "2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4",
        "status": "affected",
        "lessThan": "31f6dbb29fe17fa9595c7e8b19fd92915b03a4ca",
        "versionType": "git"
      },
      {
        "version": "2f3ebaba13cebd8badfb9aed31c0cf3cc82eb4f4",
        "status": "affected",
        "lessThan": "f5baa17a0f316c235d61623ac8e8fb32c2b3c0cc",
        "versionType": "git"
      }
    ],
    "defaultStatus": "unaffected",
    "cpes": [],
    "source": "Linux",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-99274"
  },
  {
    "vendor": "Linux",
    "name": "Linux",
    "platforms": [],
    "versions": [
      {
        "version": "5.2",
        "status": "affected"
      },
      {
        "version": "0",
        "status": "unaffected",
        "lessThan": "5.2",
        "versionType": "semver"
      },
      {
        "version": "6.12.117",
        "status": "unaffected",
        "lessThanOrEqual": "6.12.*",
        "versionType": "semver"
      },
      {
        "version": "6.18.61",
        "status": "unaffected",
        "lessThanOrEqual": "6.18.*",
        "versionType": "semver"
      },
      {
        "version": "7.3.2",
        "status": "unaffected",
        "lessThanOrEqual": "7.3.*",
        "versionType": "semver"
      },
      {
        "version": "7.4-rc1",
        "status": "unaffected",
        "lessThanOrEqual": "*",
        "versionType": "original_commit_for_fix"
      }
    ],
    "defaultStatus": "affected",
    "cpes": [],
    "source": "Linux",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-99274"
  }
]

References changed

before

[
  "https://git.kernel.org/stable/c/4a426ca5be7e3dedbe76575b967db04fbf01136f",
  "https://git.kernel.org/stable/c/31f6dbb29fe17fa9595c7e8b19fd92915b03a4ca",
  "https://git.kernel.org/stable/c/f5baa17a0f316c235d61623ac8e8fb32c2b3c0cc"
]

after

[
  "https://git.kernel.org/stable/c/8e0d425b808c367f5033eb72aa4528ae18473627",
  "https://git.kernel.org/stable/c/4a426ca5be7e3dedbe76575b967db04fbf01136f",
  "https://git.kernel.org/stable/c/31f6dbb29fe17fa9595c7e8b19fd92915b03a4ca",
  "https://git.kernel.org/stable/c/f5baa17a0f316c235d61623ac8e8fb32c2b3c0cc"
]

Environment requirements changed

before

[
  {
    "source": "Linux",
    "statements": [
      {
        "nodes": [
          {
            "operator": "OR",
            "negate": false,
            "cpeMatch": [
              {
                "vulnerable": true,
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "versionStartIncluding": "5.2",
                "versionEndExcluding": "6.18.61"
              },
              {
                "vulnerable": true,
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "versionStartIncluding": "5.2",
                "versionEndExcluding": "7.3.2"
              },
              {
                "vulnerable": true,
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "versionStartIncluding": "5.2",
                "versionEndExcluding": "7.4-rc1"
              }
            ]
          }
        ]
      }
    ]
  }
]

after

[
  {
    "source": "Linux",
    "statements": [
      {
        "nodes": [
          {
            "operator": "OR",
            "negate": false,
            "cpeMatch": [
              {
                "vulnerable": true,
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "versionStartIncluding": "5.2",
                "versionEndExcluding": "6.12.117"
              },
              {
                "vulnerable": true,
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "versionStartIncluding": "5.2",
                "versionEndExcluding": "6.18.61"
              },
              {
                "vulnerable": true,
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "versionStartIncluding": "5.2",
                "versionEndExcluding": "7.3.2"
              },
              {
                "vulnerable": true,
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "versionStartIncluding": "5.2",
                "versionEndExcluding": "7.4-rc1"
              }
            ]
          }
        ]
      }
    ]
  }
]

Large field values are marked as truncated previews. Original source snapshots remain retained.

Showing up to 50 most recent observed changes.

Reading the signals

Severity · CVSS: Technical impact and attack conditions. No numeric assessment supplied.
Observed exploitation · KEV: An absent or unavailable KEV listing does not establish that exploitation has not occurred.
Predicted exploitation · EPSS: No EPSS estimate available in this record.

Record identifiers

Aliases: None recorded

Source evidence

Request a correction or dispute

Start with the assigning organization for this record. Include the CVE ID, the disputed information, and supporting evidence. A dispute does not itself reject a record.

Find the responsible CNA →Official dispute and escalation process ↗

CVE CVE-2026-99274

Enrichment coverage

NVDAvailable

Checked 07/11/2026, 14:45:31 UTC

GHSANo result

Checked 07/11/2026, 14:45:31 UTC

EUVDNo result

Checked 07/11/2026, 14:45:31 UTC

EPSSNo result

Checked 07/11/2026, 14:45:30 UTC

Additional source evidence

NVD · CVE-2026-99274Checked 07/11/2026, 14:45:31 UTC

Sponsored by MoxsoBuild security habits with adaptive training and phishing simulations.View as JSON

smb: client: fix fiemap wild read on empty truncated response

Severity and exploitation

What this means

Attack conditions

Affected versions

Linux

affected

unaffected

unknown

Linux

affected

unaffected

unknown

What to do

Public exploit evidence

Original source description

References

Inside the record

Evidence available

Original records

Environment requirements

Timeline

Advisory published

Source updated

Last imported by cve.new

What changed