SB2026081605 - Integer underflow in Linux kernel iomap
Published: August 16, 2026
Security Bulletin ID
SB2026081605
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Integer underflow (CVE-ID: CVE-2026-72367)
CWE-ID: CWE-191 - Integer underflow
CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause data corruption.
The vulnerability exists due to an integer underflow in fs/iomap/ioend.c when handling concurrent truncate and writeback operations around EOF. A local user can trigger concurrent file append writes and truncation to cause data corruption.
The issue occurs when EOF moves to or before the ioend start offset, causing a negative size calculation to wrap to a large unsigned value.
Remediation
Install update from vendor's website.