CVE-2026-74349
Received Received - Intake

BaseFortify

Publication date: 2026-08-15

Last updated on: 2026-08-15

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: ocfs2: reject FITRIM ranges shorter than a cluster ocfs2_trim_mainbm() trims the global bitmap in cluster units, but its too-short range validation only checks sb->s_blocksize. On filesystems with a cluster size larger than the block size, a FITRIM range that is at least one block but shorter than one cluster is accepted and shifted down to len == 0. The later start + len - 1 and len -= ... arithmetic then underflows and can drive trimming past the requested range. Reject ranges shorter than s_clustersize instead. That preserves the existing -EINVAL behavior for requests that cannot discard even one allocation unit and keeps zero-cluster trims out of the group walk.

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Meta Information

Published
2026-08-15
Last Modified
2026-08-15
Generated
2026-08-15
AI Q&A
2026-08-15
EPSS Evaluated
N/A
NVD
CVE-2026-74349
EUVD
EUVD-2026-59496

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
linux_kernel ocfs2 *

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Exploitability

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CWE ID Description
CWE-UNKNOWN

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Executive Summary

This vulnerability affects the Linux kernel's OCFS2 filesystem. It involves incorrect validation of FITRIM range lengths in ocfs2_trim_mainbm(). The function trims storage in cluster units but only checks block size, not cluster size. If a filesystem has a larger cluster size than block size, a FITRIM range that is at least one block but shorter than one cluster can cause an underflow in arithmetic operations, leading to unintended trimming beyond the requested range.

Detection Guidance

This vulnerability is specific to the Linux kernel's OCFS2 filesystem. Detection requires checking the kernel version and OCFS2 configuration. Use 'uname -r' to check the kernel version and 'mount | grep ocfs2' to verify if OCFS2 is mounted. If the kernel is vulnerable, update it immediately.

Impact Analysis

This vulnerability could allow an attacker with local access to cause data corruption or unintended storage trimming on a system using OCFS2. It may result in loss of data or filesystem inconsistencies if exploited through crafted FITRIM commands.

Mitigation Strategies

Update the Linux kernel to a patched version that resolves this issue. Avoid using OCFS2 or ensure cluster size is properly configured. If OCFS2 is not critical, consider unmounting it until patched.

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