{"id":"CVE-2026-90048","published":"2026-09-16T11:17:18.140","lastModified":"2026-09-16T15:18:27.570","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: fix slab-out-of-bounds write in ni_create_attr_list()\n\nni_create_attr_list() allocates a fixed buffer of al_aligned(record_size)\n(== record_size) bytes and then walks every attribute of the primary MFT\nrecord, writing one ATTR_LIST_ENTRY per attribute and advancing the cursor\nby le_size(name_len), with no check against the end of the buffer; the\ntotal size is only computed after the loop.\n\nA minimum-size resident attribute occupies SIZEOF_RESIDENT (0x18 = 24)\nbytes on disk, but an unnamed attribute expands to le_size(0) (0x20 = 32)\nbytes in the list.  Because the number of attributes in a record is not\nbounded (mi_enum_attr() accepts arbitrarily many equal-type, nameless\nminimum-size attributes), a crafted record packed with such attributes\nproduces a list larger than record_size and overflows the heap buffer.\n\nThis is reachable from a crafted, loop-mounted NTFS image: opening the file\nand adding an attribute (e.g. via setxattr) drives ntfs_set_ea() ->\nni_insert_resident() -> ni_insert_attr() -> ni_ins_attr_ext() ->\nni_create_attr_list().\n\n  BUG: KASAN: slab-out-of-bounds in ni_create_attr_list+0xc48/0x1058\n  Write of size 4 at addr ffff000008984c00 by task setfattr/345\n   ni_create_attr_list+0xc48/0x1058\n   ni_ins_attr_ext+0x510/0x7c0\n   ni_insert_attr+0x3f8/0x70c\n   ni_insert_resident+0xc8/0x3b0\n   ntfs_set_ea+0x66c/0xd28\n   ntfs_setxattr+0x4d8/0x5b0\n   __arm64_sys_setxattr+0xa4/0x124\n  Allocated by task 345:\n   ni_create_attr_list+0x188/0x1058\n  The buggy address belongs to the cache kmalloc-1k of size 1024\n  (the write lands at object+1024).\n\nSize the buffer from the actual attributes instead of assuming a single\nrecord_size is always enough.","cvssScore":9.8,"cvssSeverity":"CRITICAL","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/7c4841e2a62794a3bab7c1ff0540580f387e377f","tags":[]},{"url":"https://git.kernel.org/stable/c/7e9aee7e4d9767cc3e423b3beecb01c7ebb6bbcd","tags":[]},{"url":"https://git.kernel.org/stable/c/a84f3db72561c4d9281c5ff721ce46b9ffa7f30e","tags":[]},{"url":"https://git.kernel.org/stable/c/d07e281f2a7710502985d6f80b95ddac8f4e81d5","tags":[]},{"url":"https://git.kernel.org/stable/c/fa2215cf451414b0512cd6f7d37a057893811f4d","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":{"summary":"The flaw in the Linux kernel's NTFS3 module allows for a slab-out-of-bounds write due to improper buffer handling, which can lead to potential kernel crashes or arbitrary code execution.","exploitability":"Exploitation requires a crafted NTFS image and the ability to add attributes to a file, making it moderately difficult. Precondition is the presence of a loop-mounted NTFS filesystem.","blast_radius":"If exploited, the vulnerability could result in a denial of service (DoS) or potentially arbitrary code execution within the kernel context, impacting the stability and security of the system.","remediation":"Upgrade to the fixed version 5.19.1 or later.","detection":"No reliable host or network indicator is derivable from the published description.","tags":["kernel","ntfs","buffer-overflow","slab-out-of-bounds"],"model":"qwen2.5:7b-instruct","analyzedAt":"2026-09-28T08:58:03.802Z"}}