{"id":"CVE-2026-80869","summary":"ntfs: bound the attribute-list entry in ntfs_read_inode_mount()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: bound the attribute-list entry in ntfs_read_inode_mount()\n\nThe $MFT attribute-list walk in ntfs_read_inode_mount() validates each\nentry only with \"(u8 *)al_entry + 6 \u003e al_end\" and\n\"(u8 *)al_entry + le16_to_cpu(al_entry-\u003elength) \u003e al_end\", but then reads\nal_entry-\u003elowest_vcn (an __le64 at offset 8) and al_entry-\u003emft_reference\n(offset 16) -- fields beyond the 6 bytes proven in range. al_entry-\u003elength\nis attacker-controlled and only required non-zero, so a short entry (e.g.\nlength 8) placed at the tail passes both checks while the lowest_vcn /\nmft_reference reads fall past al_end.\n\nal_end is ni-\u003eattr_list + attr_list_size (the on-disk size); the buffer is\nkvzalloc(round_up(attr_list_size, SECTOR_SIZE)), so the sector rounding\nusually absorbs the over-read -- but when attr_list_size is a multiple of\nSECTOR_SIZE there is no slack and a crafted $MFT attribute list produces an\nout-of-bounds read at mount time.\n\nValidate the entry with ntfs_attr_list_entry_is_valid() (added in patch\n1/3) before dereferencing it, matching the bound the other attribute-list\nwalks now use. The validator already requires the length to cover the fixed\nheader, which makes the separate \"!al_entry-\u003elength\" check redundant, so\ndrop it too.","modified":"2026-09-06T03:46:59.778403079Z","published":"2026-09-04T16:48:27.068Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80869.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/98634df5b1cb56c26299b7409227025ddb0167d8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c7a7e48e71ce915ec4cbd6e9f355590c1ecbc29a"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80869.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80869"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"1e9ea7e04472d4e5e12e58c881eaacfb3e49b669"},{"fixed":"c7a7e48e71ce915ec4cbd6e9f355590c1ecbc29a"},{"fixed":"98634df5b1cb56c26299b7409227025ddb0167d8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80869.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.1.0"},{"fixed":"7.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80869.json"}}],"schema_version":"1.9.0"}