CVE-2026-89779
Received
Received - Intake
Buffer Overflow in Linux Kernel NTFS3 Filesystem
Vulnerability report for CVE-2026-89779, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-16
Last updated on: 2026-09-16
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: validate ef->size covers the record's name and value
When an EA record has a non-zero ef->size, ntfs_read_ea() only checks
that the record fits in the remaining buffer (ea_size > bytes), not that
ef->size is large enough to hold the record's own name_len + 1 + elength.
A crafted image can pass validation with, e.g., ef->size = 24 but
elength = 0xffff. ntfs_get_ea() then trusts elength and copies it out of
the undersized record, reading past the kmalloc(info->size) allocation
and leaking heap memory to userspace via getxattr():
BUG: KASAN: slab-out-of-bounds in ntfs_get_ea (fs/ntfs3/xattr.c:302)
Read of size 65535 at addr ffff888100794550 by task exploit
__asan_memcpy (mm/kasan/shadow.c:105)
ntfs_get_ea (fs/ntfs3/xattr.c:302)
ntfs_getxattr (fs/ntfs3/xattr.c:848)
__vfs_getxattr (fs/xattr.c:441)
vfs_getxattr (fs/xattr.c:474)
do_getxattr (fs/xattr.c:800)
path_getxattrat (fs/xattr.c:868)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
The buggy address is located 80 bytes inside of
allocated 84-byte region in cache kmalloc-96
Compute the size the record needs and require ef->size to cover it.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
