Vulnerability-Lookup

CVE-2026-64388 (GCVE-0-2026-64388)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-07-25 08:50

Title

smb/client: fix chown/chgrp with SMB3 POSIX Extensions

Summary

In the Linux kernel, the following vulnerability has been resolved: smb/client: fix chown/chgrp with SMB3 POSIX Extensions Ownership (chown) and group (chgrp) modifications were being ignored when mounting with SMB3 POSIX Extensions unless CIFS_MOUNT_CIFS_ACL or CIFS_MOUNT_MODE_FROM_SID were also explicitly set. Fix this by checking for posix_extensions in cifs_setattr_nounix() when updating UID and GID, ensuring that id_mode_to_cifs_acl() is called to map and set the ownership/group information on the server.

Severity

No CVSS data available.

Assigner

Linux

References

2 references

URL	Tags
https://git.kernel.org/stable/c/550cfb8a81181331d…
https://git.kernel.org/stable/c/760ef2c579c2609cf…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 550cfb8a81181331d4d0f76ab75ee58a0bf41e3e (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 760ef2c579c2609cf17fb1cd5392f64d42d43d33 (git) Affected: 0 , < 7.1.4 (semver)
Linux	Linux	Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2-rc1 , ≤ * (original_commit_for_fix)

Show details on NVD website

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          "programFiles": [
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            },
            {
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              "versionType": "git"
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      "cpeApplicability": [
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                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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              "negate": false,
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        }
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      "providerMetadata": {
        "dateUpdated": "2026-07-25T08:50:36.202Z",
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        },
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    "cveId": "CVE-2026-64388",
    "datePublished": "2026-07-25T08:50:36.202Z",
    "dateReserved": "2026-07-19T15:36:31.784Z",
    "dateUpdated": "2026-07-25T08:50:36.202Z",
    "state": "PUBLISHED"
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    "suse_vex": {
      "aggregate_severity": "not set",
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      "cve": "CVE-2026-64388",
      "id": "CVE-2026-64388",
      "initial_release_date": "2026-07-25T16:00:17Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64388",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64388.json",
      "version": "2"
    }
  }
}

GHSA-P59X-F8QP-H8M2

Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-25 12:31

Details

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

smb/client: fix chown/chgrp with SMB3 POSIX Extensions

Ownership (chown) and group (chgrp) modifications were being ignored when mounting with SMB3 POSIX Extensions unless CIFS_MOUNT_CIFS_ACL or CIFS_MOUNT_MODE_FROM_SID were also explicitly set.

Fix this by checking for posix_extensions in cifs_setattr_nounix() when updating UID and GID, ensuring that id_mode_to_cifs_acl() is called to map and set the ownership/group information on the server.

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-64388"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-25T10:17:22Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: fix chown/chgrp with SMB3 POSIX Extensions\n\nOwnership (chown) and group (chgrp) modifications were being ignored when\nmounting with SMB3 POSIX Extensions unless CIFS_MOUNT_CIFS_ACL or\nCIFS_MOUNT_MODE_FROM_SID were also explicitly set.\n\nFix this by checking for posix_extensions in cifs_setattr_nounix() when\nupdating UID and GID, ensuring that id_mode_to_cifs_acl() is called to map\nand set the ownership/group information on the server.",
  "id": "GHSA-p59x-f8qp-h8m2",
  "modified": "2026-07-25T12:31:33Z",
  "published": "2026-07-25T12:31:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64388"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/550cfb8a81181331d4d0f76ab75ee58a0bf41e3e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/760ef2c579c2609cf17fb1cd5392f64d42d43d33"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

CVE-2026-64388 (GCVE-0-2026-64388)

GHSA-P59X-F8QP-H8M2

Tags

Sightings

Nomenclature