{"id":"CVE-2026-64395","title":"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_rang…","summary":"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_rang…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.15, < 6.1.178","linux_kernel >= 6.2, < 6.6.145","linux_kernel >= 6.7, < 6.12.96","linux_kernel >= 6.13, < 6.18.39","linux_kernel >= 6.19, < 7.1.4"],"patched":["linux_kernel 7.1.4"],"published":"2026-07-25","updated":"2026-09-04","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64395","references":[{"url":"https://git.kernel.org/stable/c/2d2ab6983620c2d60ce7db72133984ca3873b929","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/67bdad9cf01b25030e3bf00bbce6c309319d6663","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a10942af27832c2761d020863a46e79bebe0567d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b0d4d5cb846a1ddb7aaab9adfb5986e4540e6e5f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cedff600f1642aa982178503552f0d007bc829c8","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/db231af842868268839f9f9619c68cb27830d8be","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00406,"epssPercentile":0.3466,"ingestedAt":"2026-09-05T13:39:57.649Z","slug":"CVE-2026-64395","body":"## Overview\n\nIn 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.\n\n## Affected\n\n- `linux_kernel >= 5.15, < 6.1.178`\n- `linux_kernel >= 6.2, < 6.6.145`\n- `linux_kernel >= 6.7, < 6.12.96`\n- `linux_kernel >= 6.13, < 6.18.39`\n- `linux_kernel >= 6.19, < 7.1.4`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 7.1.4`","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}