CVE-2026-43129

A flaw was found in the Linux kernel's Integrity Measurement Architecture (IMA) subsystem. When a second-stage kernel is booted via kexec with a memory-limiting command line, the IMA measurement buffer from the previous kernel may fall outside the new kernel's addressable memory. This out-of-bounds access can trigger a page fault during early system restoration, potentially leading to system instability or a denial of service.

This flaw is rated as Moderate severity because exploitation is restricted to local privileged scenarios requiring explicit administrative configuration during a system reboot. On standard Red Hat Enterprise Linux systems, triggering this failure requires executing a kexec transition while passing restrictive memory bounds on the command line alongside active IMA log handover. Consequently, the issue only presents an availability concern resulting in a boot-time kernel crash, without exposing confidential data or permitting unauthorized system modifications.

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.