CVE-2026-89779: Linux

Critical severity, CVSS 9.1. EPSS: 0.7% chance of exploitation in the next 30 days.

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.

Affected products

• Linux Linux: from 5.15.121, before 5.15.221 (fixed in 5.15.221); from 6.1.40, before 6.1.188 (fixed in 6.1.188); from 6.2, before 6.6.157 (fixed in 6.6.157); from 6.7, before 6.12.110 (fixed in 6.12.110); from 6.13, before 6.18.52 (fixed in 6.18.52); from 6.19, before 7.2.6 (fixed in 7.2.6)

Published 2026-09-16. Last modified 2026-09-16.