SB20260815118 - Integer underflow in Linux kernel ocfs2
Published: August 15, 2026
Security Bulletin ID
SB20260815118
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-2026-74349)
CWE-ID: CWE-191 - Integer underflow
CVSSv4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause unintended block trimming beyond the requested range.
The vulnerability exists due to an integer underflow in ocfs2_trim_mainbm() when processing a FITRIM range shorter than a cluster. A local user can submit a specially crafted FITRIM range to cause unintended block trimming beyond the requested range.
The issue occurs on filesystems where the cluster size is larger than the block size.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/06c0a0431b9856506fcd9b2c1b0c6136567d756d
- https://git.kernel.org/stable/c/2c13e02592b918be7725ab5965e01ef4e46c4b57
- https://git.kernel.org/stable/c/346314bb0cc2fc52b50b73d6ecc62e0217455c2e
- https://git.kernel.org/stable/c/3fa7139b5f42731a61f78c42433adae13f9adc21
- https://git.kernel.org/stable/c/441abb77222f155e8d931dbabb465466db01cfd7
- https://git.kernel.org/stable/c/ca1afd88f5eaaff9168e1466e5401385edf59543
- https://git.kernel.org/stable/c/d903d59c0315f59bdf0214b4f13d71c9feb2c45c
- https://git.kernel.org/stable/c/e652d0f5108e447b22da4249bcd23dd1b63c73dd