SB20260816307 - Integer underflow in Linux kernel jbd2
Published: August 16, 2026
Security Bulletin ID
SB20260816307
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Integer underflow (CVE-ID: CVE-2026-72225)
CWE-ID: CWE-191 - Integer underflow
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to integer underflow in jbd2_journal_initialize_fast_commit() when initializing fast commit journal metadata. A local user can trigger journal initialization with crafted journal parameters to cause a denial of service.
The issue can corrupt j_last, j_fc_first, and j_free, leading to journal abort.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/289a2ca0c9b7eae74f93fc213b0b971669b8683d
- https://git.kernel.org/stable/c/4450dcaadf7d4aae8b6e4223b5d6ee4eb77097a9
- https://git.kernel.org/stable/c/4b48dcb88bb9117e3d3f051175a9a8b7cff7f8b6
- https://git.kernel.org/stable/c/78955fdce8ff654e6d33a2fa90882a1e7eb26330
- https://git.kernel.org/stable/c/a58fc10adf503969fec2007b5afe8987258046c4
- https://git.kernel.org/stable/c/e144ad0250f77e23e28949587b8b57e40dc3b512
- https://git.kernel.org/stable/c/fb9b49618ed7296ebfad62a3835da8945f727001