SB20260509105 - Improper Initialization in Linux kernel ext4
Published: May 9, 2026
Security Bulletin ID
SB20260509105
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) Improper Initialization (CVE-ID: CVE-2026-43288)
CWE-ID: CWE-665 - Improper Initialization
CVSSv4: 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/E:U/U:Clear
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper initialization in ext4 per-CPU counter handling when mounting a crafted ext4 filesystem with quota and project features enabled. A local user can mount a specially crafted filesystem image to cause a denial of service.
The issue is triggered when block bitmap validation fails during filesystem mount.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/0d5fcb063cdabb9aeaa8554b7fedad2092c4150e
- https://git.kernel.org/stable/c/270564513489d98b721a1e4a10017978d5213bff
- https://git.kernel.org/stable/c/9e9fb259bcddf459a0168f4a964e979e500a68a5
- https://git.kernel.org/stable/c/aec095f3cc6cf209effd93278ce35be27db81d73
- https://git.kernel.org/stable/c/bf5b609524497c195f801cd5707252384aed8149