CVE-2026-43271
kernel: md-cluster: fix NULL pointer dereference in process_metadata_update
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · May 6, 2026
Updated · July 3, 2026
Description
A flaw was found in the Linux kernel's md-cluster module. During the startup of a multi-device (MD) array, a race condition can occur where a remote node sends a metadata update message before the system is fully ready to process it. This premature processing leads to a null pointer dereference, causing the kernel to panic. A successful exploit could result in a Denial of Service (DoS) for the affected system.
Statement
Red Hat acknowledges the upstream Linux kernel correction for «md-cluster» as described in COMMENT_ZERO. Fixes are delivered through standard kernel errata for supported products. Operational exposure depends on whether this subsystem or driver is active in your configuration.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
To mitigate this issue, prevent the md_cluster module from being loaded. See https://access.redhat.com/solutions/41278 for instructions.
CVSS / CWE
CVSS 3.1 · 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-824 · Access of Uninitialized Pointer