SB20260816326 - Integer underflow in Linux kernel ntfs3



SB20260816326 - Integer underflow in Linux kernel ntfs3

Published: August 16, 2026

Security Bulletin ID SB20260816326
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Information disclosure

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Integer underflow (CVE-ID: CVE-2026-72195)

CWE-ID: CWE-191 - Integer underflow

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a local user to disclose sensitive information.

The vulnerability exists due to an integer underflow leading to an out-of-bounds read in do_action() UpdateResidentValue handling in fs/ntfs3/fslog.c when processing a crafted on-disk NTFS log record during mount. A local user can supply a crafted filesystem image to trigger an oversized resident attribute data_size and disclose sensitive information.

The issue occurs when attr_off and redo_len from the on-disk log record make aoff + dlen smaller than data_off, causing data_size to wrap to nearly 4 GiB.


Remediation

Install update from vendor's website.