CVE-2026-64395

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-64395", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.785Z", "datePublished": "2026-07-25T08:50:40.393Z", "dateUpdated": "2026-08-17T04:54:49.007Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:54:49.007Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: require source read access for duplicate extents\n\nFSCTL_DUPLICATE_EXTENTS_TO_FILE passes the source file directly to\nvfs_clone_file_range() or vfs_copy_file_range() without checking the SMB\naccess mask granted to the source handle. A handle opened with attribute\naccess can consequently be used to copy file contents into an\nattacker-readable destination.\n\nRequire FILE_READ_DATA on the source handle before either VFS operation,\nmatching other ksmbd data-copy paths."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "baseScore": 7.5, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:N - The vulnerable SMB2 IOCTL is remotely reachable through ksmbd over TCP, normally port 445.\nAC:L - The attacker controls both handles, offsets, and copy length; no race is required, and exploitation is reliable on common reflink-capable filesystems such as XFS and Btrfs.\nPR:N - In a reasonable guest-enabled writable-share deployment, an unauthenticated remote attacker can establish a guest session without credentials and obtain the required attribute-only source and writable destination handles.\nUI:N - After connecting to the share, the attacker can open both handles and issue the IOCTL without any victim action.\nS:U - The bypass discloses files governed by the same kernel and SMB server security authority and does not cross a virtualization or other security scope.\nC:H - Attacker-controlled offsets and lengths allow complete copying of otherwise unreadable files into an attacker-readable destination, causing total confidentiality loss for protected share contents.\nI:N - The source is not modified, and the destination must already be on a writable tree and opened with FILE_WRITE_DATA, so the flaw adds no unauthorized modification capability.\nA:N - The operation does not corrupt memory, crash the kernel, or inherently disrupt service; any destination writes are already authorized by the required handle permissions."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/smb2pdu.c"], "versions": [{"version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "lessThan": "2d2ab6983620c2d60ce7db72133984ca3873b929", "status": "affected", "versionType": "git"}, {"version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "lessThan": "67bdad9cf01b25030e3bf00bbce6c309319d6663", "status": "affected", "versionType": "git"}, {"version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "lessThan": "b0d4d5cb846a1ddb7aaab9adfb5986e4540e6e5f", "status": "affected", "versionType": "git"}, {"version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "lessThan": "db231af842868268839f9f9619c68cb27830d8be", "status": "affected", "versionType": "git"}, {"version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "lessThan": "a10942af27832c2761d020863a46e79bebe0567d", "status": "affected", "versionType": "git"}, {"version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "lessThan": "cedff600f1642aa982178503552f0d007bc829c8", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/smb2pdu.c"], "versions": [{"version": "5.15", "status": "affected"}, {"version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.96", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.39", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.4", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.1.178"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.145"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.96"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.18.39"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.1.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/2d2ab6983620c2d60ce7db72133984ca3873b929"}, {"url": "https://git.kernel.org/stable/c/67bdad9cf01b25030e3bf00bbce6c309319d6663"}, {"url": "https://git.kernel.org/stable/c/b0d4d5cb846a1ddb7aaab9adfb5986e4540e6e5f"}, {"url": "https://git.kernel.org/stable/c/db231af842868268839f9f9619c68cb27830d8be"}, {"url": "https://git.kernel.org/stable/c/a10942af27832c2761d020863a46e79bebe0567d"}, {"url": "https://git.kernel.org/stable/c/cedff600f1642aa982178503552f0d007bc829c8"}], "title": "ksmbd: require source read access for duplicate extents", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/smb/server/smb2pdu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "2d2ab6983620c2d60ce7db72133984ca3873b929", "status": "affected", "version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "versionType": "git"}, {"lessThan": "67bdad9cf01b25030e3bf00bbce6c309319d6663", "status": "affected", "version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "versionType": "git"}, {"lessThan": "b0d4d5cb846a1ddb7aaab9adfb5986e4540e6e5f", "status": "affected", "version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "versionType": "git"}, {"lessThan": "db231af842868268839f9f9619c68cb27830d8be", "status": "affected", "version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "versionType": "git"}, {"lessThan": "a10942af27832c2761d020863a46e79bebe0567d", "status": "affected", "version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "versionType": "git"}, {"lessThan": "cedff600f1642aa982178503552f0d007bc829c8", "status": "affected", "version": "eb817368f50c1cbe1bd07044124aad7db6330e3a", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/smb/server/smb2pdu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.15"}, {"lessThan": "5.15", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.178", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.145", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.96", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.39", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "489A511C-ECAA-4ACC-BE73-C261B3681C52", "versionEndExcluding": "6.1.178", "versionStartIncluding": "5.15", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "7046B092-F810-4440-ACE6-60218518EECE", "versionEndExcluding": "6.6.145", "versionStartIncluding": "6.2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "38A8100E-2B1A-462F-AEE9-8901B870FEF2", "versionEndExcluding": "6.12.96", "versionStartIncluding": "6.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "914AE4BC-3D59-4C5A-9DB5-9CE327B429F7", "versionEndExcluding": "6.18.39", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42", "versionEndExcluding": "7.1.4", "versionStartIncluding": "6.19", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: require source read access for duplicate extents\n\nFSCTL_DUPLICATE_EXTENTS_TO_FILE passes the source file directly to\nvfs_clone_file_range() or vfs_copy_file_range() without checking the SMB\naccess mask granted to the source handle. A handle opened with attribute\naccess can consequently be used to copy file contents into an\nattacker-readable destination.\n\nRequire FILE_READ_DATA on the source handle before either VFS operation,\nmatching other ksmbd data-copy paths."}], "id": "CVE-2026-64395", "lastModified": "2026-09-04T14:47:48.093", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-07-25T10:17:22.923", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2d2ab6983620c2d60ce7db72133984ca3873b929"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/67bdad9cf01b25030e3bf00bbce6c309319d6663"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a10942af27832c2761d020863a46e79bebe0567d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/b0d4d5cb846a1ddb7aaab9adfb5986e4540e6e5f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/cedff600f1642aa982178503552f0d007bc829c8"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/db231af842868268839f9f9619c68cb27830d8be"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: ksmbd: require source read access for duplicate extents", "id": "2507278", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2507278"}, "csaw": false, "cwe": "CWE-358", "details": ["A flaw was found in the Linux kernel's ksmbd component. This vulnerability allows an attacker with attribute access to a file to bypass security checks when duplicating file extents. By using the FSCTL_DUPLICATE_EXTENTS_TO_FILE function, an attacker can copy the contents of a source file to a destination that they can read, leading to information disclosure."], "name": "CVE-2026-64395", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-07-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-64395\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-64395\nhttps://lore.kernel.org/linux-cve-announce/2026072528-CVE-2026-64395-26a3@gregkh/T"]}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,2d2ab6983620c2d60ce7db72133984ca3873b929)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,67bdad9cf01b25030e3bf00bbce6c309319d6663)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,b0d4d5cb846a1ddb7aaab9adfb5986e4540e6e5f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,db231af842868268839f9f9619c68cb27830d8be)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,a10942af27832c2761d020863a46e79bebe0567d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,cedff600f1642aa982178503552f0d007bc829c8)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.1.178)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.6.145)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.12.96)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.18.39)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,7.1.4)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.1.178,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.145,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.96,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.39,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.4,8.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-07-25T16:30:06.000940+00:00", "updated": "2026-09-04T23:30:06.525970+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}