{"id":"CVE-2026-80673","summary":"ntfs: bound the look-ahead attribute-list entry in ntfs_external_attr_find()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: bound the look-ahead attribute-list entry in ntfs_external_attr_find()\n\nWhen resolving an attribute lookup with a non-zero @lowest_vcn,\nntfs_external_attr_find() peeks at the next $ATTRIBUTE_LIST entry to\ndecide whether to keep searching, but bounds that not-yet-validated\nentry only with \"(u8 *)next_al_entry + 6 \u003c al_end\" (which proves just\nbytes 0..6 are in range) and \"(u8 *)next_al_entry + length \u003c= al_end\"\nwith an attacker-controlled, non-8-aligned length. It then reads\nnext_al_entry-\u003elowest_vcn (an __le64 at offset 8) and the name at\nnext_al_entry-\u003ename_offset, both of which can lie past al_end -- the\nexact end of the kvmalloc'd attribute-list buffer (allocated at the\non-disk attr_list_size, no rounding). A crafted on-disk $ATTRIBUTE_LIST\nwhose last entry sits a few bytes before al_end therefore yields a slab\nout-of-bounds read when the inode is read.\n\nValidate the look-ahead entry with ntfs_attr_list_entry_is_valid() (added\nin patch 1/3) before dereferencing lowest_vcn and the name, so the same\nfixed-header, length and name bounds the main attribute-list walk uses now\nguard this read too.","modified":"2026-08-30T03:48:21.440947428Z","published":"2026-08-28T06:49:12.951Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80673.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/344b18f389f9934d59c7b0cf3d20541ea2e0da58"},{"type":"WEB","url":"https://git.kernel.org/stable/c/44885c9b45eb4082fb7f558590d84bb254a08e94"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80673.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80673"},{"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":"44885c9b45eb4082fb7f558590d84bb254a08e94"},{"fixed":"344b18f389f9934d59c7b0cf3d20541ea2e0da58"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80673.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-2026-80673.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}