Vulnerability-Lookup

CVE-2026-31432 (GCVE-0-2026-31432)

Vulnerability from cvelistv5 – Published: 2026-04-22 08:15 – Updated: 2026-04-22 08:15

Title

ksmbd: fix OOB write in QUERY_INFO for compound requests

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix OOB write in QUERY_INFO for compound requests When a compound request such as READ + QUERY_INFO(Security) is received, and the first command (READ) consumes most of the response buffer, ksmbd could write beyond the allocated buffer while building a security descriptor. The root cause was that smb2_get_info_sec() checked buffer space using ppntsd_size from xattr, while build_sec_desc() often synthesized a significantly larger descriptor from POSIX ACLs. This patch introduces smb_acl_sec_desc_scratch_len() to accurately compute the final descriptor size beforehand, performs proper buffer checking with smb2_calc_max_out_buf_len(), and uses exact-sized allocation + iov pinning.

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/d48c64fb80ad78b3d…
	https://git.kernel.org/stable/c/075ea208c648cc2bc…
	https://git.kernel.org/stable/c/515c2daab46021221…
	https://git.kernel.org/stable/c/fda9522ed6afaec45…

Impacted products

Vendor

Product

Version

Linux

Affected: e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d , < d48c64fb80ad78b3dd29fb7d79b6ec7bd72bfc09 (git)
Affected: e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d , < 075ea208c648cc2bcd616295b711d3637c61de45 (git)
Affected: e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d , < 515c2daab46021221bdf406bef19bc90a44ec617 (git)
Affected: e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d , < fda9522ed6afaec45cabc198d8492270c394c7bc (git)
Affected: f2283680a80571ca82d710bc6ecd8f8beac67d63 (git)
Affected: 9f297df20d93411c0b4ddad7f88ba04a7cd36e77 (git)

Linux

Affected: 6.6
Unaffected: 0 , < 6.6 (semver)
Unaffected: 6.12.81 , ≤ 6.12.* (semver)
Unaffected: 6.18.22 , ≤ 6.18.* (semver)
Unaffected: 6.19.12 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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    "datePublished": "2026-04-22T08:15:10.873Z",
    "dateReserved": "2026-03-09T15:48:24.089Z",
    "dateUpdated": "2026-04-22T08:15:10.873Z",
    "state": "PUBLISHED"
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FKIE_CVE-2026-31432

Vulnerability from fkie_nvd - Published: 2026-04-22 09:16 - Updated: 2026-04-23 16:17

Severity ?

Summary

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/075ea208c648cc2bcd616295b711d3637c61de45
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/515c2daab46021221bdf406bef19bc90a44ec617
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/d48c64fb80ad78b3dd29fb7d79b6ec7bd72bfc09
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/fda9522ed6afaec45cabc198d8492270c394c7bc

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix OOB write in QUERY_INFO for compound requests\n\nWhen a compound request such as READ + QUERY_INFO(Security) is received,\nand the first command (READ) consumes most of the response buffer,\nksmbd could write beyond the allocated buffer while building a security\ndescriptor.\n\nThe root cause was that smb2_get_info_sec() checked buffer space using\nppntsd_size from xattr, while build_sec_desc() often synthesized a\nsignificantly larger descriptor from POSIX ACLs.\n\nThis patch introduces smb_acl_sec_desc_scratch_len() to accurately\ncompute the final descriptor size beforehand, performs proper buffer\nchecking with smb2_calc_max_out_buf_len(), and uses exact-sized\nallocation + iov pinning."
    }
  ],
  "id": "CVE-2026-31432",
  "lastModified": "2026-04-23T16:17:41.280",
  "metrics": {},
  "published": "2026-04-22T09:16:21.410",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/075ea208c648cc2bcd616295b711d3637c61de45"
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/515c2daab46021221bdf406bef19bc90a44ec617"
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/d48c64fb80ad78b3dd29fb7d79b6ec7bd72bfc09"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fda9522ed6afaec45cabc198d8492270c394c7bc"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}

MSRC_CVE-2026-31432

Vulnerability from csaf_microsoft - Published: 2026-04-02 00:00 - Updated: 2026-04-23 14:38

Summary

ksmbd: fix OOB write in QUERY_INFO for compound requests

Notes

Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

CVE-2026-31432

None Available There is no fix available for this vulnerability as of now

References

URL

Category

	https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self
	https://support.microsoft.com/lifecycle	external
	https://www.first.org/cvss	external
	https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self

JSON

To clipboard

{
  "document": {
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-31432 ksmbd: fix OOB write in QUERY_INFO for compound requests - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-31432.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "ksmbd: fix OOB write in QUERY_INFO for compound requests",
    "tracking": {
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      "generator": {
        "date": "2026-04-24T07:10:38.656Z",
        "engine": {
          "name": "MSRC Generator",
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      "id": "msrc_CVE-2026-31432",
      "initial_release_date": "2026-04-02T00:00:00.000Z",
      "revision_history": [
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          "date": "2026-04-23T01:07:15.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
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          "legacy_version": "2",
          "number": "2",
          "summary": "Information published."
        }
      ],
      "status": "final",
      "version": "2"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "3.0",
                "product": {
                  "name": "Azure Linux 3.0",
                  "product_id": "17084"
                }
              }
            ],
            "category": "product_name",
            "name": "Azure Linux"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "azl3 kernel 0:6.6.130.1-3.azl3",
                "product": {
                  "name": "azl3 kernel 0:6.6.130.1-3.azl3",
                  "product_id": "1"
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            "name": "kernel"
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        "category": "vendor",
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      }
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    "relationships": [
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        "full_product_name": {
          "name": "azl3 kernel 0:6.6.130.1-3.azl3 as a component of Azure Linux 3.0",
          "product_id": "17084-1"
        },
        "product_reference": "1",
        "relates_to_product_reference": "17084"
      }
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  "vulnerabilities": [
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      "cve": "CVE-2026-31432",
      "notes": [
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          "category": "general",
          "text": "Linux",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "known_affected": [
          "17084-1"
        ]
      },
      "references": [
        {
          "category": "self",
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          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-31432.json"
        }
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      "remediations": [
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          "category": "none_available",
          "date": "2026-04-23T01:07:15.000Z",
          "details": "There is no fix available for this vulnerability as of now",
          "product_ids": [
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        }
      ],
      "title": "ksmbd: fix OOB write in QUERY_INFO for compound requests"
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}

GHSA-F75P-6Q8J-P2F2

Vulnerability from github – Published: 2026-04-22 09:31 – Updated: 2026-04-22 09:31

Details

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

ksmbd: fix OOB write in QUERY_INFO for compound requests

When a compound request such as READ + QUERY_INFO(Security) is received, and the first command (READ) consumes most of the response buffer, ksmbd could write beyond the allocated buffer while building a security descriptor.

The root cause was that smb2_get_info_sec() checked buffer space using ppntsd_size from xattr, while build_sec_desc() often synthesized a significantly larger descriptor from POSIX ACLs.

This patch introduces smb_acl_sec_desc_scratch_len() to accurately compute the final descriptor size beforehand, performs proper buffer checking with smb2_calc_max_out_buf_len(), and uses exact-sized allocation + iov pinning.

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-31432"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-22T09:16:21Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix OOB write in QUERY_INFO for compound requests\n\nWhen a compound request such as READ + QUERY_INFO(Security) is received,\nand the first command (READ) consumes most of the response buffer,\nksmbd could write beyond the allocated buffer while building a security\ndescriptor.\n\nThe root cause was that smb2_get_info_sec() checked buffer space using\nppntsd_size from xattr, while build_sec_desc() often synthesized a\nsignificantly larger descriptor from POSIX ACLs.\n\nThis patch introduces smb_acl_sec_desc_scratch_len() to accurately\ncompute the final descriptor size beforehand, performs proper buffer\nchecking with smb2_calc_max_out_buf_len(), and uses exact-sized\nallocation + iov pinning.",
  "id": "GHSA-f75p-6q8j-p2f2",
  "modified": "2026-04-22T09:31:32Z",
  "published": "2026-04-22T09:31:32Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31432"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/075ea208c648cc2bcd616295b711d3637c61de45"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/515c2daab46021221bdf406bef19bc90a44ec617"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d48c64fb80ad78b3dd29fb7d79b6ec7bd72bfc09"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fda9522ed6afaec45cabc198d8492270c394c7bc"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

Sightings

Author	Source	Type	Date

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.

Action not permitted

CVE-2026-31432 (GCVE-0-2026-31432)

FKIE_CVE-2026-31432

MSRC_CVE-2026-31432

GHSA-F75P-6Q8J-P2F2

Tags

Sightings

Nomenclature