CVE-2026-97438
Description
In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: validate index entry key bounds
[BUG]
A malformed NTFS directory index entry can advertise a key_size larger
than the bytes actually present in its NTFS_DE payload. Directory lookup
then passes that malformed key to cmp_fnames(), which can read past the
end of the kmalloc'ed index buffer.
BUG: KASAN: slab-out-of-bounds in fname_full_size fs/ntfs3/ntfs.h:590 [inline]
BUG: KASAN: slab-out-of-bounds in cmp_fnames+0x1ea/0x230 fs/ntfs3/index.c:46
Read of size 1 at addr ffff88801c313018 by task syz.6.3365/9279
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0xbe/0x130 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xd1/0x650 mm/kasan/report.c:482
kasan_report+0xfb/0x140 mm/kasan/report.c:595
__asan_report_load1_noabort+0x14/0x30 mm/kasan/report_generic.c:378
fname_full_size fs/ntfs3/ntfs.h:590 [inline]
cmp_fnames+0x1ea/0x230 fs/ntfs3/index.c:46
hdr_find_e.isra.0+0x3ed/0x670 fs/ntfs3/index.c:762
indx_find+0x4b5/0x900 fs/ntfs3/index.c:1186
dir_search_u+0x2c0/0x460 fs/ntfs3/dir.c:254
ntfs_lookup+0x1cc/0x2a0 fs/ntfs3/namei.c:85
__lookup_slow+0x241/0x450 fs/namei.c:1816
lookup_slow fs/namei.c:1833 [inline]
walk_component+0x31c/0x570 fs/namei.c:2151
link_path_walk+0x592/0xd60 fs/namei.c:2519
path_lookupat+0x138/0x660 fs/namei.c:2675
filename_lookup+0x1f3/0x560 fs/namei.c:2705
filename_setxattr+0xad/0x1c0 fs/xattr.c:660
path_setxattrat+0x1d8/0x280 fs/xattr.c:713
__do_sys_lsetxattr fs/xattr.c:754 [inline]
__se_sys_lsetxattr fs/xattr.c:750 [inline]
__x64_sys_lsetxattr+0xd0/0x150 fs/xattr.c:750
...
Allocated by task 9279:
kasan_save_stack+0x39/0x70 mm/kasan/common.c:56
kasan_save_track+0x14/0x40 mm/kasan/common.c:77
kasan_save_alloc_info+0x37/0x60 mm/kasan/generic.c:573
poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
__kasan_kmalloc+0xc3/0xd0 mm/kasan/common.c:417
kasan_kmalloc include/linux/kasan.h:262 [inline]
__do_kmalloc_node mm/slub.c:5650 [inline]
__kmalloc_noprof+0x2bd/0x900 mm/slub.c:5662
kmalloc_noprof include/linux/slab.h:961 [inline]
indx_read+0x41d/0xad0 fs/ntfs3/index.c:1059
indx_find+0x447/0x900 fs/ntfs3/index.c:1179
dir_search_u+0x2c0/0x460 fs/ntfs3/dir.c:254
ntfs_lookup+0x1cc/0x2a0 fs/ntfs3/namei.c:85
__lookup_slow+0x241/0x450 fs/namei.c:1816
lookup_slow fs/namei.c:1833 [inline]
walk_component+0x31c/0x570 fs/namei.c:2151
link_path_walk+0x592/0xd60 fs/namei.c:2519
path_lookupat+0x138/0x660 fs/namei.c:2675
filename_lookup+0x1f3/0x560 fs/namei.c:2705
filename_setxattr+0xad/0x1c0 fs/xattr.c:660
path_setxattrat+0x1d8/0x280 fs/xattr.c:713
__do_sys_lsetxattr fs/xattr.c:754 [inline]
__se_sys_lsetxattr fs/xattr.c:750 [inline]
__x64_sys_lsetxattr+0xd0/0x150 fs/xattr.c:750
...
[CAUSE]
The index-header validators only validated INDEX_HDR-level geometry.
They did not walk each NTFS_DE to verify entry alignment, subnode
layout, or that key_size fit inside the entry payload. They also
allowed a last sentinel entry to carry a non-zero key_size.
[FIX]
Walk every NTFS_DE in ntfs3's index-header validators and reject
entries with invalid layout, mismatched subnode state, oversized
key_size, or non-zero sentinel keys before lookup or log replay can
consume them.
EPSS (Exploit Prediction Scoring System)
EPSS (Exploit Prediction Scoring System)
Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.
Single Data Point
Only one EPSS measurement is available for this CVE. Trend analysis requires multiple data points over time.