CVE-2026-64395 (GCVE-0-2026-64395)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-08-17 04:54
VLAI
Title
ksmbd: require source read access for duplicate extents
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: require source read access for duplicate extents FSCTL_DUPLICATE_EXTENTS_TO_FILE passes the source file directly to vfs_clone_file_range() or vfs_copy_file_range() without checking the SMB access mask granted to the source handle. A handle opened with attribute access can consequently be used to copy file contents into an attacker-readable destination. Require FILE_READ_DATA on the source handle before either VFS operation, matching other ksmbd data-copy paths.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: eb817368f50c1cbe1bd07044124aad7db6330e3a , < 2d2ab6983620c2d60ce7db72133984ca3873b929 (git)
Affected: eb817368f50c1cbe1bd07044124aad7db6330e3a , < 67bdad9cf01b25030e3bf00bbce6c309319d6663 (git)
Affected: eb817368f50c1cbe1bd07044124aad7db6330e3a , < b0d4d5cb846a1ddb7aaab9adfb5986e4540e6e5f (git)
Affected: eb817368f50c1cbe1bd07044124aad7db6330e3a , < db231af842868268839f9f9619c68cb27830d8be (git)
Affected: eb817368f50c1cbe1bd07044124aad7db6330e3a , < a10942af27832c2761d020863a46e79bebe0567d (git)
Affected: eb817368f50c1cbe1bd07044124aad7db6330e3a , < cedff600f1642aa982178503552f0d007bc829c8 (git)
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Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.96 , ≤ 6.12.* (semver)
Unaffected: 6.18.39 , ≤ 6.18.* (semver)
Unaffected: 7.1.4 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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    "dateReserved": "2026-07-19T15:36:31.785Z",
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    "state": "PUBLISHED"
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                "integrityImpact": "NONE",
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      "cve": "CVE-2026-64395",
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      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: ksmbd: require source read access for duplicate extents",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64395.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-15T01:50:07Z",
      "cve": "CVE-2026-64395",
      "id": "CVE-2026-64395",
      "initial_release_date": "2026-07-25T16:00:09Z",
      "product_status:known_affected": "125",
      "product_status:known_not_affected": "251",
      "product_status:recommended": "4",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64395",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64395.json",
      "version": "7"
    }
  }
}



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  • 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.
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  • 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.


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