CVE-2026-98135

In the Linux kernel, the following vulnerability has been resolved: ntfs: reject invalid sectors_per_cluster in the boot sector is_boot_sector_ntfs() checks the boot sector's sectors_per_cluster field with a range test that rejects 0x81..0xf3 but accepts 0 and other non-power-of-two counts. A zero value reaches parse_ntfs_boot_sector(): sectors_per_cluster_bits = ffs(sectors_per_cluster) - 1; ... vol->cluster_size = vol->sector_size << sectors_per_cluster_bits; ffs(0) is 0, so sectors_per_cluster_bits becomes (unsigned)-1 and the shift is undefined: UBSAN: shift-out-of-bounds in fs/ntfs/super.c:673:39 shift exponent 4294967295 is too large for 32-bit type 'int' This change rejects any non-power-of-two value, since it feeds the aforementioned shift via ffs() - 1, which only yields the correct shift for a power of two.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/323751a604e7533fa473874d999371592a614207	Patch
https://git.kernel.org/stable/c/7524c3145a3bac92bebbc47a29c007f1d874c9b3	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.3:rc1::::::

History

08 Oct 2026, 18:11

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.5
First Time		Linux Linux linux Kernel
CPE		cpe:2.3:o:linux:linux_kernel:::::::: cpe:2.3:o:linux:linux_kernel:7.3:rc1::::::
CWE		NVD-CWE-noinfo
References	~~() https://git.kernel.org/stable/c/323751a604e7533fa473874d999371592a614207 -~~	() https://git.kernel.org/stable/c/323751a604e7533fa473874d999371592a614207 - Patch
References	~~() https://git.kernel.org/stable/c/7524c3145a3bac92bebbc47a29c007f1d874c9b3 -~~	() https://git.kernel.org/stable/c/7524c3145a3bac92bebbc47a29c007f1d874c9b3 - Patch

25 Sep 2026, 11:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-25 11:17

Updated : 2026-10-19 10:18

NVD link : CVE-2026-98135

Mitre link : CVE-2026-98135

CVE.ORG link : CVE-2026-98135

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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